Added an experiment for an LRU snapshot cache.

ios/chrome/ios_chrome.gyp

 # Copyright 2014 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': [
     {
@@ skipping 391 matching lines @@
         'browser/signin/signin_client_factory.h',
         'browser/signin/signin_client_impl.cc',
         'browser/signin/signin_client_impl.h',
         'browser/signin/signin_error_controller_factory.cc',
         'browser/signin/signin_error_controller_factory.h',
         'browser/signin/signin_manager_factory.cc',
         'browser/signin/signin_manager_factory.h',
         'browser/signin/signin_manager_factory_observer.h',
         'browser/signin/signin_util.h',
         'browser/signin/signin_util.mm',
+        'browser/snapshots/lru_cache.h',
+        'browser/snapshots/lru_cache.mm',
         'browser/snapshots/snapshot_cache.h',
         'browser/snapshots/snapshot_cache.mm',
         'browser/snapshots/snapshot_manager.h',
         'browser/snapshots/snapshot_manager.mm',
         'browser/snapshots/snapshot_overlay.h',
         'browser/snapshots/snapshot_overlay.mm',
         'browser/snapshots/snapshots_util.h',
         'browser/snapshots/snapshots_util.mm',
         'browser/suggestions/image_fetcher_impl.h',
         'browser/suggestions/image_fetcher_impl.mm',
@@ skipping 240 matching lines @@
             '../../components/components.gyp:omnibox_browser',
             '../../components/components.gyp:rlz',
             '../../components/components.gyp:search_engines',
             '../../rlz/rlz.gyp:rlz_lib',
           ],
         },
       ],
     }],
   ],
 }