Move webkit/blob to new locations.

webkit/common/webkit_common.gypi

 # 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.
 
 {
   'includes': [
+    '../common/blob/webkit_common_blob.gypi',
     '../common/database/webkit_common_database.gypi',
   ],
   # TODO(michaeln): Have webkit_browser target and deprecate old gypis like
   # webkit_storage.gypi.
   'variables': {
     'webkit_common_storage_sources': [
+      '<@(webkit_common_blob_sources)',
       '<@(webkit_common_database_sources)',
     ],
   },
 }