Make ShortcutsBackend a ProfileKeyedService.

chrome/chrome_browser.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.
 
 {
   'targets': [
     {
       'target_name': 'browser',
       'type': 'static_library',
@@ skipping 1155 matching lines @@
         'browser/history/page_usage_data.cc',
         'browser/history/page_usage_data.h',
         'browser/history/query_parser.cc',
         'browser/history/query_parser.h',
         'browser/history/scored_history_match.cc',
         'browser/history/scored_history_match.h',
         'browser/history/snippet.cc',
         'browser/history/snippet.h',
         'browser/history/shortcuts_backend.cc',
         'browser/history/shortcuts_backend.h',
+        'browser/history/shortcuts_backend_factory.cc',
+        'browser/history/shortcuts_backend_factory.h',
         'browser/history/shortcuts_database.cc',
         'browser/history/shortcuts_database.h',
         'browser/history/starred_url_database.cc',
         'browser/history/starred_url_database.h',
         'browser/history/text_database.cc',
         'browser/history/text_database.h',
         'browser/history/text_database_manager.cc',
         'browser/history/text_database_manager.h',
         'browser/history/thumbnail_database.cc',
         'browser/history/thumbnail_database.h',
@@ skipping 4158 matching lines @@
         'browser/metrics/proto/study.proto',
       ],
       'variables': {
         'proto_in_dir': 'browser/metrics/proto',
         'proto_out_dir': 'chrome/browser/metrics/proto',
       },
       'includes': [ '../build/protoc.gypi' ]
     },
   ],
 }