--- a/Cargo.lock
+++ b/Cargo.lock
@@ -731,59 +731,59 @@ name = "crossbeam-utils"
 version = "0.6.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "cssparser"
-version = "0.25.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "cssparser-macros 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+version = "0.25.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cssparser-macros 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "dtoa-short 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "itoa 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "phf 0.7.21 (registry+https://github.com/rust-lang/crates.io-index)",
  "proc-macro2 0.4.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "procedural-masquerade 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 0.6.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "syn 0.15.30 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "cssparser-macros"
-version = "0.3.3"
+version = "0.3.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "phf_codegen 0.7.21 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro2 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 0.4.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "procedural-masquerade 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "quote 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.13.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 0.6.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.30 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "cstr"
 version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "cstr-macros 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cstr-macros 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "procedural-masquerade 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "cstr-macros"
-version = "0.1.3"
+version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "procedural-masquerade 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.13.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.30 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "cubeb"
 version = "0.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cubeb-core 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1199,17 +1199,17 @@ dependencies = [
  "zip 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "geckoservo"
 version = "0.0.1"
 dependencies = [
  "atomic_refcell 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.25.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.25.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "cstr 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.51 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "malloc_size_of 0.0.1",
  "nsstring 0.1.0",
  "num-traits 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "selectors 0.21.0",
@@ -1676,17 +1676,17 @@ name = "lzw"
 version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "malloc_size_of"
 version = "0.0.1"
 dependencies = [
  "app_units 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.25.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.25.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.19.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "hashglobe 0.1.0",
  "selectors 0.21.0",
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  "smallbitvec 2.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "thin-slice 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1841,18 +1841,18 @@ dependencies = [
  "xpcom 0.1.0",
 ]
 
 [[package]]
 name = "mozilla-central-workspace-hack"
 version = "0.1.0"
 dependencies = [
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro2 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "quote 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 0.4.27 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 0.6.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.88 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.88 (git+https://github.com/servo/serde?branch=deserialize_from_enums10)",
  "syn 0.15.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.6 (git+https://github.com/froydnj/winapi-rs?branch=aarch64)",
 ]
 
 [[package]]
@@ -2013,23 +2013,22 @@ dependencies = [
 name = "nsstring-gtest"
 version = "0.1.0"
 dependencies = [
  "nsstring 0.1.0",
 ]
 
 [[package]]
 name = "num-derive"
-version = "0.2.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "num-traits 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
  "proc-macro2 0.4.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 0.6.11 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.14.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.30 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "num-integer"
 version = "0.1.39"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "num-traits 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2246,24 +2245,16 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "prefs_parser"
 version = "0.0.1"
 
 [[package]]
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-version = "0.3.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "proc-macro2"
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 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "procedural-masquerade"
@@ -2297,24 +2288,16 @@ dependencies = [
 
 [[package]]
 name = "quick-error"
 version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "quote"
-version = "0.5.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "proc-macro2 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "quote"
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 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 0.4.27 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "rand"
@@ -2662,17 +2645,17 @@ dependencies = [
  "syn 0.15.30 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
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 version = "0.21.0"
 dependencies = [
  "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.25.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.25.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "derive_more 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "fxhash 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
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  "precomputed-hash 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "servo_arc 0.1.1",
@@ -2879,33 +2862,33 @@ name = "style"
 version = "0.0.1"
 dependencies = [
  "app_units 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "arrayvec 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
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  "byteorder 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.25.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.25.5 (registry+https://github.com/rust-lang/crates.io-index)",
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  "euclid 0.19.5 (registry+https://github.com/rust-lang/crates.io-index)",
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  "nsstring 0.1.0",
- "num-derive 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-derive 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
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  "num-traits 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
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@@ -2941,33 +2924,33 @@ dependencies = [
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 [[package]]
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  "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "cssparser 0.25.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.25.5 (registry+https://github.com/rust-lang/crates.io-index)",
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 [[package]]
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- "cssparser 0.25.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.25.5 (registry+https://github.com/rust-lang/crates.io-index)",
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@@ -2980,36 +2963,16 @@ dependencies = [
 
 [[package]]
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 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
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-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
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- "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
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-
-[[package]]
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-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
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- "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
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-
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 dependencies = [
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  "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -3132,17 +3095,17 @@ dependencies = [
  "redox_syscall 0.1.32 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.6 (git+https://github.com/froydnj/winapi-rs?branch=aarch64)",
 ]
 
 [[package]]
 name = "to_shmem"
 version = "0.0.1"
 dependencies = [
- "cssparser 0.25.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cssparser 0.25.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "servo_arc 0.1.1",
  "smallbitvec 2.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
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  "thin-slice 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "to_shmem_derive"
@@ -3691,18 +3654,19 @@ dependencies = [
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 ]
 
 [[package]]
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 version = "0.1.0"
 dependencies = [
  "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "quote 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.13.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 0.4.27 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 0.6.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.30 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
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 dependencies = [
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@@ -3802,20 +3766,20 @@ dependencies = [
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 "checksum crossbeam-deque 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f739f8c5363aca78cfb059edf753d8f0d36908c348f3d8d1503f03d8b75d9cf3"
 "checksum crossbeam-deque 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "fe8153ef04a7594ded05b427ffad46ddeaf22e63fd48d42b3e1e3bb4db07cae7"
 "checksum crossbeam-epoch 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "927121f5407de9956180ff5e936fe3cf4324279280001cd56b669d28ee7e9150"
 "checksum crossbeam-epoch 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2af0e75710d6181e234c8ecc79f14a97907850a541b13b0be1dd10992f2e4620"
 "checksum crossbeam-utils 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "2760899e32a1d58d5abb31129f8fae5de75220bc2176e77ff7c627ae45c918d9"
 "checksum crossbeam-utils 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "d636a8b3bcc1b409d7ffd3facef8f21dcb4009626adbd0c5e6c4305c07253c7b"
 "checksum crossbeam-utils 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)" = "41ee4864f4797060e52044376f7d107429ce1fb43460021b126424b7180ee21a"
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 "checksum cubeb-core 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)" = "0161f9327864922ba7a172c90bd86bc9094938433eca415e2c75629954045022"
 "checksum cubeb-sys 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)" = "3ba7540c17b90159cf7d7854da370998ff0560d9b90e2c9290bb588afa0edf95"
 "checksum darling 0.8.6 (registry+https://github.com/rust-lang/crates.io-index)" = "9158d690bc62a3a57c3e45b85e4d50de2008b39345592c64efd79345c7e24be0"
 "checksum darling_core 0.8.6 (registry+https://github.com/rust-lang/crates.io-index)" = "d2a368589465391e127e10c9e3a08efc8df66fd49b87dc8524c764bbe7f2ef82"
 "checksum darling_macro 0.8.6 (registry+https://github.com/rust-lang/crates.io-index)" = "244e8987bd4e174385240cde20a3657f607fb0797563c28255c353b5819a07b1"
 "checksum deflate 0.7.19 (registry+https://github.com/rust-lang/crates.io-index)" = "8a6abb26e16e8d419b5c78662aa9f82857c2386a073da266840e474d5055ec86"
@@ -3909,17 +3873,17 @@ dependencies = [
 "checksum mp4parse_fallible 0.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "6626c2aef76eb8f984eef02e475883d3fe9112e114720446c5810fc5f045cd30"
 "checksum msdos_time 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "aad9dfe950c057b1bfe9c1f2aa51583a8468ef2a5baba2ebbe06d775efeb7729"
 "checksum murmurhash3 0.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "a2983372caf4480544083767bf2d27defafe32af49ab4df3a0b7fc90793a3664"
 "checksum net2 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)" = "42550d9fb7b6684a6d404d9fa7250c2eb2646df731d1c06afc06dcee9e1bcf88"
 "checksum new_debug_unreachable 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0cdc457076c78ab54d5e0d6fa7c47981757f1e34dc39ff92787f217dede586c4"
 "checksum nodrop 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)" = "9a2228dca57108069a5262f2ed8bd2e82496d2e074a06d1ccc7ce1687b6ae0a2"
 "checksum nom 3.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "05aec50c70fd288702bcd93284a8444607f3292dbdf2a30de5ea5dcdbe72287b"
 "checksum nom 4.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "9c349f68f25f596b9f44cf0e7c69752a5c633b0550c3ff849518bfba0233774a"
-"checksum num-derive 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "0d2c31b75c36a993d30c7a13d70513cb93f02acafdd5b7ba250f9b0e18615de7"
+"checksum num-derive 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)" = "eafd0b45c5537c3ba526f79d3e75120036502bebacbb3f3220914067ce39dbf2"
 "checksum num-integer 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)" = "e83d528d2677f0518c570baf2b7abdcf0cd2d248860b68507bdcb3e91d4c0cea"
 "checksum num-iter 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)" = "af3fdbbc3291a5464dc57b03860ec37ca6bf915ed6ee385e7c6c052c422b2124"
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 "checksum num-traits 0.1.43 (registry+https://github.com/rust-lang/crates.io-index)" = "92e5113e9fd4cc14ded8e499429f396a20f98c772a47cc8622a736e1ec843c31"
 "checksum num-traits 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "0b3a5d7cc97d6d30d8b9bc8fa19bf45349ffe46241e8816f50f62f6d6aaabee1"
 "checksum num_cpus 1.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "514f0d73e64be53ff320680ca671b64fe3fb91da01e1ae2ddc99eb51d453b20d"
 "checksum object 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)" = "6cca6ad89d0801138cb4ef606908ae12d83edc4c790ef5178fc7b4c72d959e90"
 "checksum opaque-debug 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "51ecbcb821e1bd256d456fe858aaa7f380b63863eab2eb86eee1bd9f33dd6682"
@@ -3938,21 +3902,19 @@ dependencies = [
 "checksum phf_shared 0.7.21 (registry+https://github.com/rust-lang/crates.io-index)" = "07e24b0ca9643bdecd0632f2b3da6b1b89bbb0030e0b992afc1113b23a7bc2f2"
 "checksum pkg-config 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)" = "3a8b4c6b8165cd1a1cd4b9b120978131389f64bdaf456435caa41e630edba903"
 "checksum plain 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "b4596b6d070b27117e987119b4dac604f3c58cfb0b191112e24771b2faeac1a6"
 "checksum plane-split 0.13.8 (registry+https://github.com/rust-lang/crates.io-index)" = "91c621d83b9c5a85b7ca7ca2bec643136debb327ad29d0a08768db1325780365"
 "checksum plist 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "95bef0807b4fe77618f8d24f0c4ec37a4ad1dad9348c3b27d8b624c824d8cf48"
 "checksum png 0.14.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9adebf7fb91ccf5eac9da1a8e00e83cb8ae882c3e8d8e4ad59da73cb8c82a2c9"
 "checksum podio 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "e5422a1ee1bc57cc47ae717b0137314258138f38fd5f3cea083f43a9725383a0"
 "checksum precomputed-hash 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "925383efa346730478fb4838dbe9137d2a47675ad789c546d150a6e1dd4ab31c"
-"checksum proc-macro2 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "77997c53ae6edd6d187fec07ec41b207063b5ee6f33680e9fa86d405cdd313d4"
 "checksum proc-macro2 0.4.27 (registry+https://github.com/rust-lang/crates.io-index)" = "4d317f9caece796be1980837fd5cb3dfec5613ebdb04ad0956deea83ce168915"
 "checksum procedural-masquerade 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "9f566249236c6ca4340f7ca78968271f0ed2b0f234007a61b66f9ecd0af09260"
 "checksum quick-error 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "eda5fe9b71976e62bc81b781206aaa076401769b2143379d3eb2118388babac4"
-"checksum quote 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9949cfe66888ffe1d53e6ec9d9f3b70714083854be20fd5e271b232a017401e8"
 "checksum quote 0.6.11 (registry+https://github.com/rust-lang/crates.io-index)" = "cdd8e04bd9c52e0342b406469d494fcb033be4bdbe5c606016defbb1681411e1"
 "checksum rand 0.3.22 (registry+https://github.com/rust-lang/crates.io-index)" = "15a732abf9d20f0ad8eeb6f909bf6868722d9a06e1e50802b6a70351f40b4eb1"
 "checksum rand 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "8356f47b32624fef5b3301c1be97e5944ecdd595409cc5da11d05f211db6cfbd"
 "checksum rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)" = "6d71dacdc3c88c1fde3885a3be3fbab9f35724e6ce99467f7d9c5026132184ca"
 "checksum rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "556d3a1ca6600bfcbab7c7c91ccb085ac7fbbcd70e008a98742e7847f4f7bcef"
 "checksum rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6fdeb83b075e8266dcc8762c22776f6877a63111121f5f8c7411e5be7eed4b"
 "checksum rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d0e7a549d590831370895ab7ba4ea0c1b6b011d106b5ff2da6eee112615e6dc0"
 "checksum rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7b40677c7be09ae76218dc623efbf7b18e34bced3f38883af07bb75630a21bc4"
@@ -4004,18 +3966,16 @@ dependencies = [
 "checksum smallvec 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)" = "622df2d454c29a4d89b30dc3b27b42d7d90d6b9e587dbf8f67652eb7514da484"
 "checksum stable_deref_trait 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "15132e0e364248108c5e2c02e3ab539be8d6f5d52a01ca9bbf27ed657316f02b"
 "checksum string 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "00caf261d6f90f588f8450b8e1230fa0d5be49ee6140fdfbcb55335aff350970"
 "checksum string_cache 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)" = "25d70109977172b127fe834e5449e5ab1740b9ba49fa18a2020f509174f25423"
 "checksum string_cache_codegen 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "1eea1eee654ef80933142157fdad9dd8bc43cf7c74e999e369263496f04ff4da"
 "checksum string_cache_shared 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b1884d1bc09741d466d9b14e6d37ac89d6909cbcac41dd9ae982d4d063bbedfc"
 "checksum strsim 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bb4f380125926a99e52bc279241539c018323fab05ad6368b56f93d9369ff550"
 "checksum svg_fmt 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c666f0fed8e1e20e057af770af9077d72f3d5a33157b8537c1475dd8ffd6d32b"
-"checksum syn 0.13.1 (registry+https://github.com/rust-lang/crates.io-index)" = "91b52877572087400e83d24b9178488541e3d535259e04ff17a63df1e5ceff59"
-"checksum syn 0.14.6 (registry+https://github.com/rust-lang/crates.io-index)" = "4e4b5274d4a0a3d2749d5c158dc64d3403e60554dc61194648787ada5212473d"
 "checksum syn 0.15.30 (registry+https://github.com/rust-lang/crates.io-index)" = "66c8865bf5a7cbb662d8b011950060b3c8743dca141b054bf7195b20d314d8e2"
 "checksum synstructure 0.10.1 (registry+https://github.com/rust-lang/crates.io-index)" = "73687139bf99285483c96ac0add482c3776528beac1d97d444f6e91f203a2015"
 "checksum target-lexicon 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1b0ab4982b8945c35cc1c46a83a9094c414f6828a099ce5dcaa8ee2b04642dcb"
 "checksum tempfile 3.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "47776f63b85777d984a50ce49d6b9e58826b6a3766a449fc95bc66cd5663c15b"
 "checksum term 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "fa63644f74ce96fbeb9b794f66aff2a52d601cbd5e80f4b97123e3899f4570f1"
 "checksum term_size 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e2b6b55df3198cc93372e85dd2ed817f0e38ce8cc0f22eb32391bfad9c4bf209"
 "checksum termcolor 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "adc4587ead41bf016f11af03e55a624c06568b5a19db4e90fde573d805074f83"
 "checksum termion 1.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "689a3bdfaab439fd92bc87df5c4c78417d3cbe537487274e9b0b2dce76e92096"

--- a/build/workspace-hack/Cargo.toml
+++ b/build/workspace-hack/Cargo.toml
@@ -14,18 +14,18 @@ version = "0.1.0"
 # by dependencies in each cargo invocation for each instance they would differ.
 
 [build-dependencies]
 void = { features = ["std", "default"], version = "1.0.2" }
 syn = { features = ["clone-impls", "default", "derive", "extra-traits", "full", "parsing", "printing", "proc-macro", "quote", "visit"],  version = "0.15" }
 log = { features = ["release_max_level_info", "release_max_level_warn", "std"],  version = "0.4.6" }
 serde = { features = ["default", "rc", "serde_derive", "std"], version = "1.0.66" }
 serde_derive = { features = ["default", "deserialize_in_place"], version = "1.0.66" }
-quote = { features = ["default", "proc-macro"], version = "0.5.2" }
-proc-macro2 = { features = ["default", "proc-macro"], version = "0.3.5" }
+quote = { features = ["default", "proc-macro"], version = "0.6.11" }
+proc-macro2 = { features = ["default", "proc-macro"], version = "0.4.27" }
 
 [target."cfg(windows)".dependencies.winapi]
 version = "0.3.6"
 features = [
     "basetsd",
     "consoleapi",
     "dwrite",
     "dwrite_1",

--- a/xpcom/rust/xpcom/xpcom_macros/Cargo.toml
+++ b/xpcom/rust/xpcom/xpcom_macros/Cargo.toml
@@ -2,11 +2,12 @@
 name = "xpcom_macros"
 version = "0.1.0"
 authors = ["Michael Layzell <michael@thelayzells.com>"]
 
 [lib]
 proc-macro = true
 
 [dependencies]
-syn = "0.13"
-quote = "0.5"
+syn = "0.15"
+quote = "0.6"
+proc-macro2 = "0.4"
 lazy_static = "1.0"

--- a/xpcom/rust/xpcom/xpcom_macros/src/lib.rs
+++ b/xpcom/rust/xpcom/xpcom_macros/src/lib.rs
@@ -145,25 +145,27 @@
 #![recursion_limit="256"]
 
 #[macro_use]
 extern crate quote;
 
 extern crate syn;
 
 extern crate proc_macro;
+extern crate proc_macro2;
 
 #[macro_use]
 extern crate lazy_static;
 
 use proc_macro::TokenStream;
 
-use quote::{ToTokens, Tokens};
+use quote::ToTokens;
+use proc_macro2::{Span, TokenStream as TokenStream2};
 
-use syn::*;
+use syn::{parse, parse_quote, Attribute, Data, DataStruct, DeriveInput, Field, Fields, Ident, Lit, Meta, NestedMeta, Token, Type};
 
 use syn::punctuated::Punctuated;
 
 use std::collections::{HashMap, HashSet};
 use std::error::Error;
 
 /* These are the structs generated by the rust_macros.py script */
 
@@ -224,29 +226,29 @@ lazy_static! {
 #[derive(Debug, Eq, PartialEq, Copy, Clone)]
 enum RefcntKind {
     Atomic,
     NonAtomic,
 }
 
 /// Produces the tokens for the type representation.
 impl ToTokens for RefcntKind {
-    fn to_tokens(&self, tokens: &mut Tokens) {
+    fn to_tokens(&self, tokens: &mut TokenStream2) {
         match *self {
             RefcntKind::NonAtomic => quote!(xpcom::Refcnt).to_tokens(tokens),
             RefcntKind::Atomic => quote!(xpcom::AtomicRefcnt).to_tokens(tokens),
         }
     }
 }
 
 /// Scans through the attributes on a struct, and extracts the type of the refcount to use.
 fn get_refcnt_kind(attrs: &[Attribute]) -> Result<RefcntKind, Box<Error>> {
     for attr in attrs {
         if let Some(Meta::NameValue(ref attr)) = attr.interpret_meta() {
-            if attr.ident.as_ref() != "refcnt" {
+            if attr.ident != "refcnt" {
                 continue;
             }
 
             let value = if let Lit::Str(ref s) = attr.lit {
                 s.value()
             } else {
                 Err("Unexpected non-string value in #[refcnt]")?
             };
@@ -267,23 +269,23 @@ fn get_refcnt_kind(attrs: &[Attribute]) 
 
 /// Scan the attributes looking for an #[xpimplements] attribute. The identifier
 /// arguments passed to this attribute are the interfaces which the type wants to
 /// directly implement.
 fn get_bases(attrs: &[Attribute]) -> Result<Vec<&'static Interface>, Box<Error>> {
     let mut inherits = Vec::new();
     for attr in attrs {
         if let Some(Meta::List(ref attr)) = attr.interpret_meta() {
-            if attr.ident.as_ref() != "xpimplements" {
+            if attr.ident != "xpimplements" {
                 continue;
             }
 
             for item in &attr.nested {
                 if let NestedMeta::Meta(Meta::Word(ref iface)) = *item {
-                    if let Some(&iface) = IFACES.get(iface.as_ref()) {
+                    if let Some(&iface) = IFACES.get(iface.to_string().as_str()) {
                         inherits.push(iface);
                     } else {
                         Err(format!("Unexpected invalid base interface `{}` in \
                                      #[xpimplements(..)]", iface))?
                     }
                 } else {
                     Err("Unexpected non-identifier in #[xpimplements(..)]")?
                 }
@@ -303,25 +305,25 @@ fn get_fields(di: &DeriveInput) -> Resul
                   named value struct definition".into())
     }
 }
 
 /// Takes the `Init*` struct in, and generates a `DeriveInput` for the "real" struct.
 fn gen_real_struct(init: &DeriveInput, bases: &[&Interface], refcnt_ty: RefcntKind) -> Result<DeriveInput, Box<Error>> {
     // Determine the name for the real struct based on the name of the
     // initializer struct's name.
-    if !init.ident.as_ref().starts_with("Init") {
+    if !init.ident.to_string().starts_with("Init") {
         Err("The target struct's name must begin with Init")?
     }
-    let name: Ident = init.ident.as_ref()[4..].into();
+    let name: Ident = Ident::new(&init.ident.to_string()[4..], Span::call_site());
     let vis = &init.vis;
 
     let bases = bases.iter().map(|base| {
-        let ident = Ident::from(format!("__base_{}", base.name));
-        let vtable = Ident::from(format!("{}VTable", base.name));
+        let ident = Ident::new(&format!("__base_{}", base.name), Span::call_site());
+        let vtable = Ident::new(&format!("{}VTable", base.name), Span::call_site());
         quote!(#ident : *const xpcom::interfaces::#vtable)
      });
 
     let fields = get_fields(init)?;
     Ok(parse_quote! {
         #[repr(C)]
         #vis struct #name {
             #(#bases,)*
@@ -332,38 +334,38 @@ fn gen_real_struct(init: &DeriveInput, b
 }
 
 /// Generates the `extern "system"` methods which are actually included in the
 /// VTable for the given interface.
 ///
 /// These methods attempt to invoke the `recover_self` method to translate from
 /// the passed-in raw pointer to the actual `&self` value, and it is expected to
 /// be in scope.
-fn gen_vtable_methods(iface: &Interface) -> Result<Tokens, Box<Error>> {
-    let base_ty = Ident::from(iface.name);
+fn gen_vtable_methods(iface: &Interface) -> Result<TokenStream2, Box<Error>> {
+    let base_ty = Ident::new(iface.name, Span::call_site());
 
     let base_methods = if let Some(base) = iface.base()? {
         gen_vtable_methods(base)?
     } else {
         quote!{}
     };
 
     let methods = iface.methods
         .map_err(|reason| format!("Interface {} cannot be implemented in rust \
                                    because {} is not supported yet", iface.name, reason))?;
 
     let mut method_defs = Vec::new();
     for method in methods {
-        let name = Ident::from(method.name);
+        let name = Ident::new(method.name, Span::call_site());
         let ret = syn::parse_str::<Type>(method.ret)?;
 
         let mut params = Vec::new();
         let mut args = Vec::new();
         for param in method.params {
-            let name = Ident::from(param.name);
+            let name = Ident::new(param.name, Span::call_site());
             let ty = syn::parse_str::<Type>(param.ty)?;
 
             params.push(quote!{#name : #ty,});
             args.push(quote!{#name,});
         }
 
         method_defs.push(quote!{
             unsafe extern "system" fn #name (this: *const #base_ty, #(#params)*) -> #ret {
@@ -376,46 +378,46 @@ fn gen_vtable_methods(iface: &Interface)
     Ok(quote!{
         #base_methods
         #(#method_defs)*
     })
 }
 
 /// Generates the VTable for a given base interface. This assumes that the
 /// implementations of each of the `extern "system"` methods are in scope.
-fn gen_inner_vtable(iface: &Interface) -> Result<Tokens, Box<Error>> {
-    let vtable_ty = Ident::from(format!("{}VTable", iface.name));
+fn gen_inner_vtable(iface: &Interface) -> Result<TokenStream2, Box<Error>> {
+    let vtable_ty = Ident::new(&format!("{}VTable", iface.name), Span::call_site());
 
     let methods = iface.methods
         .map_err(|reason| format!("Interface {} cannot be implemented in rust \
                                    because {} is not supported yet", iface.name, reason))?;
 
     // Generate the vtable for the base interface.
     let base_vtable = if let Some(base) = iface.base()? {
         let vt = gen_inner_vtable(base)?;
         quote!{__base: #vt,}
     } else {
         quote!{}
     };
 
     // Include each of the method definitions for this interface.
     let vtable_init = methods.into_iter().map(|method| {
-        let name = Ident::from(method.name);
+        let name = Ident::new(method.name, Span::call_site());
         quote!{ #name : #name , }
     }).collect::<Vec<_>>();
 
     Ok(quote!(#vtable_ty {
         #base_vtable
         #(#vtable_init)*
     }))
 }
 
-fn gen_root_vtable(name: &Ident, base: &Interface) -> Result<Tokens, Box<Error>> {
-    let field = Ident::from(format!("__base_{}", base.name));
-    let vtable_ty = Ident::from(format!("{}VTable", base.name));
+fn gen_root_vtable(name: &Ident, base: &Interface) -> Result<TokenStream2, Box<Error>> {
+    let field = Ident::new(&format!("__base_{}", base.name), Span::call_site());
+    let vtable_ty = Ident::new(&format!("{}VTable", base.name), Span::call_site());
     let methods = gen_vtable_methods(base)?;
     let value = gen_inner_vtable(base)?;
 
     // Define the `recover_self` method. This performs an offset calculation to
     // recover a pointer to the original struct from a pointer to the given
     // VTable field.
     Ok(quote!{#field: {
         // NOTE: The &'a () dummy lifetime parameter is useful as it easily
@@ -450,17 +452,17 @@ fn gen_root_vtable(name: &Ident, base: &
 /// value is the `QueryInterface` implementation, and the second is the `Coerce`
 /// implementation.
 fn gen_casts(
     seen: &mut HashSet<&'static str>,
     iface: &Interface,
     name: &Ident,
     coerce_name: &Ident,
     vtable_field: &Ident,
-) -> Result<(Tokens, Tokens), Box<Error>> {
+) -> Result<(TokenStream2, TokenStream2), Box<Error>> {
     if !seen.insert(iface.name) {
         return Ok((quote!{}, quote!{}));
     }
 
     // Generate the cast implementations for the base interfaces.
     let (base_qi, base_coerce) = if let Some(base) = iface.base()? {
         gen_casts(
             seen,
@@ -469,17 +471,17 @@ fn gen_casts(
             coerce_name,
             vtable_field,
         )?
     } else {
         (quote!{}, quote!{})
     };
 
     // Add the if statment to QueryInterface for the base class.
-    let base_name = Ident::from(iface.name);
+    let base_name = Ident::new(iface.name, Span::call_site());
 
     let qi = quote! {
         #base_qi
         if *uuid == #base_name::IID {
             // Implement QueryInterface in terms of coersions.
             self.addref();
             *result = self.coerce::<#base_name>()
                 as *const #base_name
@@ -506,17 +508,17 @@ fn gen_casts(
             }
         }
     };
 
     Ok((qi, coerce))
 }
 
 /// The root xpcom procedural macro definition.
-fn xpcom(init: DeriveInput) -> Result<Tokens, Box<Error>> {
+fn xpcom(init: DeriveInput) -> Result<TokenStream2, Box<Error>> {
     if !init.generics.params.is_empty() || !init.generics.where_clause.is_none() {
         return Err("Cannot #[derive(xpcom)] on a generic type, due to \
                     rust limitations. It is not possible to instantiate \
                     a static with a generic type parameter, meaning that \
                     generic types cannot have their VTables instantiated \
                     correctly.".into());
     }
 
@@ -529,17 +531,17 @@ fn xpcom(init: DeriveInput) -> Result<To
     }
 
     // Determine what reference count type to use, and generate the real struct.
     let refcnt_ty = get_refcnt_kind(&init.attrs)?;
     let real = gen_real_struct(&init, &bases, refcnt_ty)?;
 
     let name_init = &init.ident;
     let name = &real.ident;
-    let coerce_name = Ident::from(format!("{}Coerce", name.as_ref()));
+    let coerce_name = Ident::new(&format!("{}Coerce", name.to_string()), Span::call_site());
 
     // Generate a VTable for each of the base interfaces.
     let mut vtables = Vec::new();
     for base in &bases {
         vtables.push(gen_root_vtable(name, base)?);
     }
 
     // Generate the field initializers for the final struct, moving each field
@@ -556,17 +558,17 @@ fn xpcom(init: DeriveInput) -> Result<To
     let mut qi_impl = Vec::new();
     let mut coerce_impl = Vec::new();
     for base in &bases {
         let (qi, coerce) = gen_casts(
             &mut seen,
             base,
             name,
             &coerce_name,
-            &Ident::from(format!("__base_{}", base.name)),
+            &Ident::new(&format!("__base_{}", base.name), Span::call_site()),
         )?;
         qi_impl.push(qi);
         coerce_impl.push(coerce);
     }
 
     Ok(quote! {
         #real