Move webkit_common to its own gyp file

webkit/common/webkit_common.gyp

 # Copyright 2013 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': {
+    'enable_wexit_time_destructors': 1,
+    'chromium_code': 1
+  },
   'targets': [
     {
       'target_name': 'webkit_common',
       'type': '<(component)',
-      'variables': { 'enable_wexit_time_destructors': 1, },
       'defines': [
         'WEBKIT_COMMON_IMPLEMENTATION',
       ],
       'dependencies': [
         '<(DEPTH)/base/base.gyp:base_i18n',
         '<(DEPTH)/base/base.gyp:base',
         '<(DEPTH)/base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
         '<(DEPTH)/net/net.gyp:net',
         '<(DEPTH)/skia/skia.gyp:skia',
         '<(DEPTH)/ui/ui.gyp:ui',
@@ skipping 58 matching lines @@
           'sources/': [['exclude', '_win\\.cc$']],
         }, {  # else: OS=="win"
           # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
           'msvs_disabled_warnings': [ 4800, 4267 ],
           'sources/': [['exclude', '_posix\\.cc$']],
         }],
       ],
     },
   ],
 }