Add some src/webkit build files to the GN build.

webkit/storage_browser.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': {
     'chromium_code': 1,
   },
   'targets': [
     {
+      # GN version: //webkit/browser:storage
       'target_name': 'webkit_storage_browser',
       'type': '<(component)',
       'variables': { 'enable_wexit_time_destructors': 1, },
       'dependencies': [
         '<(DEPTH)/base/base.gyp:base',
         '<(DEPTH)/base/base.gyp:base_i18n',
         '<(DEPTH)/base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
         '<(DEPTH)/net/net.gyp:net',
         '<(DEPTH)/sql/sql.gyp:sql',
         '<(DEPTH)/third_party/leveldatabase/leveldatabase.gyp:leveldatabase',
@@ skipping 198 matching lines @@
         }],
         ['OS=="android"', {
           'defines': ['APPCACHE_USE_SIMPLE_CACHE'],
           'direct_dependent_settings': {
             'defines': ['APPCACHE_USE_SIMPLE_CACHE'],
           },
         }],
       ],
     },
     {
+      # GN version: //webkit/browser:dump_file_system
       'target_name': 'dump_file_system',
       'type': 'executable',
       'sources': [
         'browser/fileapi/dump_file_system.cc',
       ],
       'dependencies': [
         '<(DEPTH)/base/base.gyp:base',
         '<(DEPTH)/webkit/storage_common.gyp:webkit_storage_common',
         'webkit_storage_browser',
       ],
     },
   ],
 }