ui: Cache the output of View::OnPaint when the View isn't invalid.

ui/compositor/compositor.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 47 matching lines @@
         'layer_animator.cc',
         'layer_animator.h',
         'layer_animator_collection.cc',
         'layer_animator_collection.h',
         'layer_delegate.h',
         'layer_owner.cc',
         'layer_owner.h',
         'layer_tree_owner.cc',
         'layer_tree_owner.h',
         'layer_type.h',
+        'paint_cache.cc',
+        'paint_cache.h',
         'paint_context.cc',
         'paint_context.h',
         'paint_recorder.cc',
         'paint_recorder.h',
         'reflector.cc',
         'reflector.h',
         'scoped_animation_duration_scale_mode.cc',
         'scoped_animation_duration_scale_mode.h',
         'scoped_layer_animation_settings.cc',
         'scoped_layer_animation_settings.h',
@@ skipping 107 matching lines @@
               'dependencies': [
                 '<(DEPTH)/base/allocator/allocator.gyp:allocator',
               ],
             }],
           ],
         }],
       ],
     },
   ],
 }