[DevTools] Fix problem with loading source maps

third_party/WebKit/Source/devtools/front_end/devtools.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /* eslint-disable indent */
 (function(window) {
 
 // DevToolsAPI ----------------------------------------------------------------
 
 /**
@@ skipping 285 matching lines @@
      * @param {string} panelName
      */
     showPanel: function(panelName)
     {
         this._dispatchOnInspectorFrontendAPI("showPanel", [panelName]);
     },
 
     /**
      * @param {number} id
      * @param {string} chunk
+     * @param {boolean} encoded
      */
-    streamWrite: function(id, chunk)
+    streamWrite: function(id, chunk, encoded)
     {
-        this._dispatchOnInspectorFrontendAPI("streamWrite", [id, chunk]);
+        this._dispatchOnInspectorFrontendAPI("streamWrite", [id, encoded ? this._decodeBase64(chunk) : chunk]);
+    },
+
+    /**
+     * @param {string} chunk
+     * @return {string}
+     */
+    _decodeBase64: function(chunk)
+    {
+        var request = new XMLHttpRequest();
+        request.open("GET", "data:text/plain;base64," + chunk, false);
+        request.send(null);
+        if (request.status === 200) {
+            return request.responseText;
+        } else {
+            console.error("Error while decoding chunk in streamWrite");
+            return "";
+        }
     }
 }
 
 var DevToolsAPI = new DevToolsAPIImpl();
 window.DevToolsAPI = DevToolsAPI;
 
 // InspectorFrontendHostImpl --------------------------------------------------
 
 /**
  * @constructor
@@ skipping 733 matching lines @@
 
 if (!DOMTokenList.prototype.__originalDOMTokenListToggle) {
     DOMTokenList.prototype.__originalDOMTokenListToggle = DOMTokenList.prototype.toggle;
     DOMTokenList.prototype.toggle = function(token, force)
     {
         if (arguments.length === 1)
             force = !this.contains(token);
         return this.__originalDOMTokenListToggle(token, !!force);
     }
 }