Allow for building content_shell from within WebKit

content/content_shell.gypi

 # 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.
 
 {
   'variables': {
     'content_shell_product_name': 'Content Shell',
   },
   'targets': [
     {
@@ skipping 15 matching lines @@
         'content_utility',
         'content_worker',
         'content_resources.gyp:content_resources',
         '../base/base.gyp:base',
         '../base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
         '../build/temp_gyp/googleurl.gyp:googleurl',
         '../ipc/ipc.gyp:ipc',
         '../media/media.gyp:media',
         '../net/net.gyp:net',
         '../skia/skia.gyp:skia',
-        '../third_party/WebKit/Source/WebKit/chromium/WebKit.gyp:webkit',
+        '<(webkit_src_dir)/Source/WebKit/chromium/WebKit.gyp:webkit',
         '../ui/ui.gyp:ui',
         '../v8/tools/gyp/v8.gyp:v8',
         '../webkit/support/webkit_support.gyp:appcache',
         '../webkit/support/webkit_support.gyp:database',
         '../webkit/support/webkit_support.gyp:fileapi',
         '../webkit/support/webkit_support.gyp:glue',
         '../webkit/support/webkit_support.gyp:quota',
       ],
       'include_dirs': [
         '..',
@@ skipping 537 matching lines @@
                 '-buildfile',
                 '<(DEPTH)/content/shell/android/content_shell_apk.xml',
               ]
             }
           ],
         },
       ],
     }],  # OS=="android"
   ]
 }