Ensure WebKit is initialized in the case Loaded IPC arrives before UpdateUserScripts

chrome/renderer/extensions/dispatcher.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/renderer/extensions/dispatcher.h"
 
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/string_piece.h"
@@ skipping 476 matching lines @@
     }
   }
 
   if (!platform_app_patterns.empty()) {
     // We have collected a set of platform-app extensions, so let's tell WebKit
     // about them so that it can provide a default stylesheet for them.
     //
     // TODO(miket): consider enhancing WebView to allow removing
     // single stylesheets, or else to edit the pattern set associated
     // with one.
+    RenderThread::Get()->EnsureWebKitInitialized();
     WebVector<WebString> patterns;
     patterns.assign(platform_app_patterns);
     WebView::addUserStyleSheet(
         WebString::fromUTF8(ResourceBundle::GetSharedInstance().
             GetRawDataResource(IDR_PLATFORM_APP_CSS,
                                ui::SCALE_FACTOR_NONE)),
         patterns,
         WebView::UserContentInjectInAllFrames,
         WebView::UserStyleInjectInExistingDocuments);
   }
@@ skipping 603 matching lines @@
   // we should abort.
   WebKit::WebFrame* frame = context->web_frame();
   ExtensionURLInfo url_info(frame->document().securityOrigin(),
       UserScriptSlave::GetDataSourceURLForFrame(frame));
   CHECK(!extensions_.IsSandboxedPage(url_info));
 
   return true;
 }
 
 }  // namespace extensions