cc: Replace Region with SimpleEnclosedRegion for occlusion tracking

cc/cc.gyp

 # 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.
 
 {
   'variables': {
     'chromium_code': 1,
   },
   'targets': [
     {
@@ skipping 65 matching lines @@
         'base/math_util.cc',
         'base/math_util.h',
         'base/ref_counted_managed.h',
         'base/region.cc',
         'base/region.h',
         'base/rolling_time_delta_history.cc',
         'base/rolling_time_delta_history.h',
         'base/scoped_ptr_algorithm.h',
         'base/scoped_ptr_deque.h',
         'base/scoped_ptr_vector.h',
+        'base/simple_enclosed_region.cc',
+        'base/simple_enclosed_region.h',
         'base/swap_promise.h',
         'base/swap_promise_monitor.cc',
         'base/swap_promise_monitor.h',
         'base/switches.cc',
         'base/switches.h',
         'base/tiling_data.cc',
         'base/tiling_data.h',
         'base/unique_notifier.cc',
         'base/unique_notifier.h',
         'base/util.h',
@@ skipping 426 matching lines @@
         'surfaces/surface_id_allocator.h',
         'surfaces/surface_manager.cc',
         'surfaces/surface_manager.h',
         'surfaces/surface_resource_holder.cc',
         'surfaces/surface_resource_holder.h',
         'surfaces/surfaces_export.h',
       ],
     },
   ],
 }