DevTools: promisify ContentProvider.requestContent and all its clients.

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

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 36 matching lines @@
 
 WebInspector.ContentProviderBasedProject.prototype = {
     /**
      * @override
      * @param {!WebInspector.UISourceCode} uiSourceCode
      * @param {function(?string)} callback
      */
     requestFileContent: function(uiSourceCode, callback)
     {
         var contentProvider = this._contentProviders[uiSourceCode.url()];
-        contentProvider.requestContent(callback);
-
-        /**
-         * @param {?string} content
-         * @param {boolean} encoded
-         * @param {string} mimeType
-         */
-        function innerCallback(content, encoded, mimeType)
-        {
-            callback(content);
-        }
+        contentProvider.requestContent().then(callback);
     },
 
     /**
      * @override
      * @return {boolean}
      */
     canSetFileContent: function()
     {
         return false;
     },
@@ skipping 244 matching lines @@
     },
 
     dispose: function()
     {
         this._contentProviders = {};
         this.removeProject();
     },
 
     __proto__: WebInspector.ProjectStore.prototype
 }