--- a/dom/indexedDB/test/helpers.js
+++ b/dom/indexedDB/test/helpers.js
@@ -39,17 +39,17 @@ function clearAllDatabases(callback) {
   let request = qms.clearStoragesForPrincipal(principal);
   let cb = SpecialPowers.wrapCallback(callback);
   request.callback = cb;
 }
 
 var testHarnessGenerator = testHarnessSteps();
 testHarnessGenerator.next();
 
-function testHarnessSteps() {
+function* testHarnessSteps() {
   function nextTestHarnessStep(val) {
     testHarnessGenerator.next(val);
   }
 
   let testScriptPath;
   let testScriptFilename;
 
   let scripts = document.getElementsByTagName("script");

--- a/dom/indexedDB/test/unit/test_bad_origin_directory.js
+++ b/dom/indexedDB/test/unit/test_bad_origin_directory.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const url = "ftp://ftp.example.com";
   const name = "test_bad_origin_directory.js";
 
   let ios = SpecialPowers.Cc["@mozilla.org/network/io-service;1"]
                          .getService(SpecialPowers.Ci.nsIIOService);
 
   let uri = ios.newURI(url);

--- a/dom/indexedDB/test/unit/test_bug1056939.js
+++ b/dom/indexedDB/test/unit/test_bug1056939.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const dbName1 = "upgrade_test";
   const dbName2 = "testing.foobar";
   const dbName3 = "xxxxxxx.xxxxxx";
 
   clearAllDatabases(continueToNextStepSync);
   yield undefined;
 

--- a/dom/indexedDB/test/unit/test_cleanup_transaction.js
+++ b/dom/indexedDB/test/unit/test_cleanup_transaction.js
@@ -2,17 +2,17 @@
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var disableWorkerTest = "Need a way to set temporary prefs from a worker";
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const spec = "http://foo.com";
   const name =
     this.window ? window.location.pathname : "test_quotaExceeded_recovery";
   const objectStoreName = "foo";
 
   // We want 32 MB database, but there's the group limit so we need to
   // multiply by 5.

--- a/dom/indexedDB/test/unit/test_cursor_cycle.js
+++ b/dom/indexedDB/test/unit/test_cursor_cycle.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const Bob = { ss: "237-23-7732", name: "Bob" };
 
   let request = indexedDB.open(this.window ? window.location.pathname : "Splendid Test", 1);
   request.onerror = errorHandler;
   request.onupgradeneeded = grabEventAndContinueHandler;
   let event = yield undefined;
 

--- a/dom/indexedDB/test/unit/test_database_close_without_onclose.js
+++ b/dom/indexedDB/test/unit/test_database_close_without_onclose.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const name = this.window ? window.location.pathname :
                              "test_database_close_without_onclose.js";
 
   const checkpointSleepTimeSec = 10;
 
   let openRequest = indexedDB.open(name, 1);
   openRequest.onerror = errorHandler;

--- a/dom/indexedDB/test/unit/test_defaultStorageUpgrade.js
+++ b/dom/indexedDB/test/unit/test_defaultStorageUpgrade.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const openParams = [
     // This one lives in storage/default/http+++localhost
     { url: "http://localhost", dbName: "dbA", dbVersion: 1 },
 
     // This one lives in storage/default/http+++www.mozilla.org
     { url: "http://www.mozilla.org", dbName: "dbB", dbVersion: 1 },
 

--- a/dom/indexedDB/test/unit/test_file_copy_failure.js
+++ b/dom/indexedDB/test/unit/test_file_copy_failure.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const name = "test_file_copy_failure.js";
   const objectStoreName = "Blobs";
   const blob = getBlob(getView(1024));
 
   info("Opening database");
 
   let request = indexedDB.open(name);

--- a/dom/indexedDB/test/unit/test_globalObjects_ipc.js
+++ b/dom/indexedDB/test/unit/test_globalObjects_ipc.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   // Test for IDBKeyRange and indexedDB availability in ipcshell.
   run_test_in_child("./GlobalObjectsChild.js", function() {
     do_test_finished();
     continueToNextStep();
   });
   yield undefined;
 

--- a/dom/indexedDB/test/unit/test_globalObjects_other.js
+++ b/dom/indexedDB/test/unit/test_globalObjects_other.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   let ioService =
     Cc["@mozilla.org/network/io-service;1"].getService(Ci.nsIIOService);
 
   function getSpec(filename) {
     let file = do_get_file(filename);
     let uri = ioService.newFileURI(file);
     return uri.spec;

--- a/dom/indexedDB/test/unit/test_globalObjects_xpc.js
+++ b/dom/indexedDB/test/unit/test_globalObjects_xpc.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const name = "Splendid Test";
 
   // Test for IDBKeyRange and indexedDB availability in xpcshell.
   let keyRange = IDBKeyRange.only(42);
   ok(keyRange, "Got keyRange");
 
   let request = indexedDB.open(name, 1);

--- a/dom/indexedDB/test/unit/test_idbSubdirUpgrade.js
+++ b/dom/indexedDB/test/unit/test_idbSubdirUpgrade.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const openParams = [
     // This one lives in storage/default/http+++www.mozilla.org
     { url: "http://www.mozilla.org", dbName: "dbB", dbVersion: 1 },
 
     // This one lives in storage/default/1007+t+https+++developer.cdn.mozilla.net
     { appId: 1007, inIsolatedMozBrowser: true, url: "https://developer.cdn.mozilla.net",
       dbName: "dbN", dbVersion: 1 },

--- a/dom/indexedDB/test/unit/test_idle_maintenance.js
+++ b/dom/indexedDB/test/unit/test_idle_maintenance.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   let uri = Cc["@mozilla.org/network/io-service;1"].
             getService(Ci.nsIIOService).
             newURI("https://www.example.com");
   let ssm = Cc["@mozilla.org/scriptsecuritymanager;1"]
               .getService(Ci.nsIScriptSecurityManager);
   let principal = ssm.createCodebasePrincipal(uri, {});
 

--- a/dom/indexedDB/test/unit/test_invalidate.js
+++ b/dom/indexedDB/test/unit/test_invalidate.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const databaseName =
     ("window" in this) ? window.location.pathname : "Test";
 
   let dbCount = 0;
 
   // Test invalidating during a versionchange transaction.
   info("Opening database " + ++dbCount);

--- a/dom/indexedDB/test/unit/test_metadata2Restore.js
+++ b/dom/indexedDB/test/unit/test_metadata2Restore.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const openParams = [
     // This one lives in storage/permanent/chrome
     // The .metadata-v2 file was intentionally removed for this origin directory
     // to test restoring.
     { dbName: "dbA",
       dbOptions: { version: 1, storage: "persistent" } },
 

--- a/dom/indexedDB/test/unit/test_metadataRestore.js
+++ b/dom/indexedDB/test/unit/test_metadataRestore.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const openParams = [
     // This one lives in storage/permanent/chrome
     { dbName: "dbA",
       dbOptions: { version: 1, storage: "persistent" } },
 
     // This one lives in storage/temporary/http+++localhost
     { url: "http://localhost", dbName: "dbB",

--- a/dom/indexedDB/test/unit/test_mutableFileUpgrade.js
+++ b/dom/indexedDB/test/unit/test_mutableFileUpgrade.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const dbNames = [
     "No files",
     "Blobs and mutable files"
   ]
   const version = 1;
   const objectStoreName = "test";
 

--- a/dom/indexedDB/test/unit/test_oldDirectories.js
+++ b/dom/indexedDB/test/unit/test_oldDirectories.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   // This lives in storage/default/http+++www.mozilla.org
   const url = "http://www.mozilla.org";
   const dbName = "dbC";
   const dbVersion = 1;
 
   let ios = SpecialPowers.Cc["@mozilla.org/network/io-service;1"]
                          .getService(SpecialPowers.Ci.nsIIOService);

--- a/dom/indexedDB/test/unit/test_open_for_principal.js
+++ b/dom/indexedDB/test/unit/test_open_for_principal.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const name = this.window ? window.location.pathname : "Splendid Test";
 
   const objectStoreName = "Foo";
 
   const data = { key: 1, value: "bar" };
 
   let request = indexedDB.open(name, 1);

--- a/dom/indexedDB/test/unit/test_persistenceType.js
+++ b/dom/indexedDB/test/unit/test_persistenceType.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const name = "Splendid Test";
   const version = 1;
 
   const objectStoreName = "Foo";
   const data = { key: 1, value: "bar" };
 
   try {

--- a/dom/indexedDB/test/unit/test_quotaExceeded_recovery.js
+++ b/dom/indexedDB/test/unit/test_quotaExceeded_recovery.js
@@ -2,17 +2,17 @@
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var disableWorkerTest = "Need a way to set temporary prefs from a worker";
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const spec = "http://foo.com";
   const name =
     this.window ? window.location.pathname : "test_quotaExceeded_recovery";
   const objectStoreName = "foo";
 
   const android = mozinfo.os == "android";
 

--- a/dom/indexedDB/test/unit/test_schema18upgrade.js
+++ b/dom/indexedDB/test/unit/test_schema18upgrade.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const testName = "schema18upgrade";
   const testKeys = [
     -1/0,
     -1.7e308,
     -10000,
     -2,
     -1.5,

--- a/dom/indexedDB/test/unit/test_schema21upgrade.js
+++ b/dom/indexedDB/test/unit/test_schema21upgrade.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const testName = "schema21upgrade";
   const testKeys = [
     -1/0,
     -1.7e308,
     -10000,
     -2,
     -1.5,

--- a/dom/indexedDB/test/unit/test_schema23upgrade.js
+++ b/dom/indexedDB/test/unit/test_schema23upgrade.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const openParams = [
     // This one lives in storage/default/http+++www.mozilla.org
     { url: "http://www.mozilla.org", dbName: "dbB", dbVersion: 1 },
 
     // This one lives in storage/default/1007+t+https+++developer.cdn.mozilla.net
     { appId: 1007, inIsolatedMozBrowser: true, url: "https://developer.cdn.mozilla.net",
       dbName: "dbN", dbVersion: 1 },

--- a/dom/indexedDB/test/unit/test_snappyUpgrade.js
+++ b/dom/indexedDB/test/unit/test_snappyUpgrade.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const name = "test_snappyUpgrade.js";
   const objectStoreName = "test";
   const testString = "Lorem ipsum his ponderum delicatissimi ne, at noster dolores urbanitas pro, cibo elaboraret no his. Ea dicunt maiorum usu. Ad appareat facilisis mediocritatem eos. Tale graeci mentitum in eos, hinc insolens at nam. Graecis nominavi aliquyam eu vix. Id solet assentior sadipscing pro. Et per atqui graecis, usu quot viris repudiandae ei, mollis evertitur an nam. At nam dolor ignota, liber labore omnesque ea mei, has movet voluptaria in. Vel an impetus omittantur. Vim movet option salutandi ex, ne mei ignota corrumpit. Mucius comprehensam id per. Est ea putant maiestatis.";
 
   info("Installing profile");
 
   clearAllDatabases(continueToNextStepSync);

--- a/dom/indexedDB/test/unit/test_storagePersistentUpgrade.js
+++ b/dom/indexedDB/test/unit/test_storagePersistentUpgrade.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const openParams = [
     // This one lives in storage/default/http+++www.mozilla.org
     { url: "http://www.mozilla.org", dbName: "dbB", dbVersion: 1 },
 
     // This one lives in storage/default/1007+t+https+++developer.cdn.mozilla.net
     { appId: 1007, inIsolatedMozBrowser: true, url: "https://developer.cdn.mozilla.net",
       dbName: "dbN", dbVersion: 1 },

--- a/dom/indexedDB/test/unit/test_temporary_storage.js
+++ b/dom/indexedDB/test/unit/test_temporary_storage.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const name = this.window ?
                window.location.pathname :
                "test_temporary_storage.js";
   const finalVersion = 2;
 
   const tempStorageLimitKB = 1024;
   const checkpointSleepTimeSec = 5;

--- a/dom/indexedDB/test/unit/test_wasm_recompile.js
+++ b/dom/indexedDB/test/unit/test_wasm_recompile.js
@@ -1,16 +1,16 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const name = "test_wasm_recompile.js";
 
   const objectStoreName = "Wasm";
 
   const wasmData = { key: 1, wasm: null };
 
   // The goal of this test is to prove that wasm is recompiled and the on-disk

--- a/dom/indexedDB/test/unit/test_writer_starvation.js
+++ b/dom/indexedDB/test/unit/test_writer_starvation.js
@@ -7,17 +7,17 @@ if (!this.window) {
   this.runTest = function() {
     todo(false, "Test disabled in xpcshell test suite for now");
     finishTest();
   }
 }
 
 var testGenerator = testSteps();
 
-function testSteps()
+function* testSteps()
 {
   const name = this.window ? window.location.pathname : "Splendid Test";
 
   // Needs to be enough to saturate the thread pool.
   const SYNC_REQUEST_COUNT = 25;
 
   let request = indexedDB.open(name, 1);
   request.onerror = errorHandler;