--- a/toolkit/devtools/Loader.jsm
+++ b/toolkit/devtools/Loader.jsm
@@ -45,28 +45,29 @@ let loaderGlobals = {
 var BuiltinProvider = {
   load: function() {
     this.loader = new loader.Loader({
       modules: {
         "toolkit/loader": loader,
         "source-map": SourceMap,
       },
       paths: {
+        // When you add a line to this mapping, don't forget to make a
+        // corresponding addition to the SrcdirProvider mapping below as well.
         "": "resource://gre/modules/commonjs/",
         "main": "resource:///modules/devtools/main.js",
         "devtools": "resource:///modules/devtools",
         "devtools/server": "resource://gre/modules/devtools/server",
         "devtools/toolkit/webconsole": "resource://gre/modules/devtools/toolkit/webconsole",
         "devtools/app-actor-front": "resource://gre/modules/devtools/app-actor-front.js",
         "devtools/styleinspector/css-logic": "resource://gre/modules/devtools/styleinspector/css-logic",
         "devtools/css-color": "resource://gre/modules/devtools/css-color",
         "devtools/client": "resource://gre/modules/devtools/client",
 
-        "escodegen/escodegen": "resource://gre/modules/devtools/escodegen/escodegen",
-        "escodegen/package.json": "resource://gre/modules/devtools/escodegen/package.json",
+        "escodegen": "resource://gre/modules/devtools/escodegen",
         "estraverse": "resource://gre/modules/devtools/escodegen/estraverse",
 
         // Allow access to xpcshell test items from the loader.
         "xpcshell-test": "resource://test"
       },
       globals: loaderGlobals
     });
 
@@ -88,38 +89,44 @@ var SrcdirProvider = {
     return Services.io.newFileURI(file).spec;
   },
 
   load: function() {
     let srcdir = Services.prefs.getComplexValue("devtools.loader.srcdir",
                                                 Ci.nsISupportsString);
     srcdir = OS.Path.normalize(srcdir.data.trim());
     let devtoolsDir = OS.Path.join(srcdir, "browser", "devtools");
+    let toolkitDir = OS.Path.join(srcdir, "toolkit", "devtools");
+    let mainURI = this.fileURI(OS.Path.join(devtoolsDir, "main.js"));
     let devtoolsURI = this.fileURI(devtoolsDir);
-    let toolkitURI = this.fileURI(OS.Path.join(srcdir, "toolkit", "devtools"));
-    let serverURI = this.fileURI(OS.Path.join(srcdir, "toolkit", "devtools", "server"));
-    let webconsoleURI = this.fileURI(OS.Path.join(srcdir, "toolkit", "devtools", "webconsole"));
-    let appActorURI = this.fileURI(OS.Path.join(srcdir, "toolkit", "devtools", "apps", "app-actor-front.js"));
-    let cssLogicURI = this.fileURI(OS.Path.join(toolkitURI, "styleinspector", "css-logic"));
-    let clientURI = this.fileURI(OS.Path.join(srcdir, "toolkit", "devtools", "client"));
-    let mainURI = this.fileURI(OS.Path.join(srcdir, "browser", "devtools", "main.js"));
+    let serverURI = this.fileURI(OS.Path.join(toolkitDir, "server"));
+    let webconsoleURI = this.fileURI(OS.Path.join(toolkitDir, "webconsole"));
+    let appActorURI = this.fileURI(OS.Path.join(toolkitDir, "apps", "app-actor-front.js"));
+    let cssLogicURI = this.fileURI(OS.Path.join(toolkitDir, "styleinspector", "css-logic"));
+    let cssColorURI = this.fileURI(OS.Path.join(toolkitDir, "css-color"));
+    let clientURI = this.fileURI(OS.Path.join(toolkitDir, "client"));
+    let escodegenURI = this.fileURI(OS.Path.join(toolkitDir, "escodegen"));
+    let estraverseURI = this.fileURI(OS.Path.join(toolkitDir, "escodegen", "estraverse"));
     this.loader = new loader.Loader({
       modules: {
         "toolkit/loader": loader,
         "source-map": SourceMap,
       },
       paths: {
         "": "resource://gre/modules/commonjs/",
+        "main": mainURI,
+        "devtools": devtoolsURI,
         "devtools/server": serverURI,
         "devtools/toolkit/webconsole": webconsoleURI,
         "devtools/app-actor-front": appActorURI,
+        "devtools/styleinspector/css-logic": cssLogicURI,
+        "devtools/css-color": cssColorURI,
         "devtools/client": clientURI,
-        "devtools": devtoolsURI,
-        "devtools/styleinspector/css-logic": cssLogicURI,
-        "main": mainURI
+        "escodegen": escodegenURI,
+        "estraverse": estraverseURI
       },
       globals: loaderGlobals
     });
 
     return this._writeManifest(devtoolsDir).then(null, Cu.reportError);
   },
 
   unload: function(reason) {