cc: Simplify the logic for deciding to update tile priorities.

cc/picture_layer_tiling.cc

 // Copyright 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.
 
 #include "cc/picture_layer_tiling.h"
 
 #include "base/debug/trace_event.h"
 #include "cc/math_util.h"
 #include "ui/gfx/point_conversions.h"
 #include "ui/gfx/rect_conversions.h"
@@ skipping 346 matching lines @@
     float last_layer_contents_scale,
     float current_layer_contents_scale,
     const gfx::Transform& last_screen_transform,
     const gfx::Transform& current_screen_transform,
     int current_source_frame_number,
     double current_frame_time,
     bool store_screen_space_quads_on_tiles) {
   if (ContentRect().IsEmpty())
     return;
 
-  bool first_update_in_new_source_frame =
-      current_source_frame_number != last_source_frame_number_;
-
-  bool first_update_in_new_impl_frame =
-      current_frame_time != last_impl_frame_time_;
-
-  // In pending tree, this is always called. We update priorities:
-  // - Immediately after a commit (first_update_in_new_source_frame).
-  // - On animation ticks after the first frame in the tree
-  //   (first_update_in_new_impl_frame).
-  // In active tree, this is only called during draw. We update priorities:
-  // - On draw if properties were not already computed by the pending tree
-  //   and activated for the frame (first_update_in_new_impl_frame).
-  if (!first_update_in_new_impl_frame && !first_update_in_new_source_frame)
+  if (!needs_update_tile_priorities(current_source_frame_number,
+                                    current_frame_time))
     return;
 
   double time_delta = 0;
   if (last_impl_frame_time_ != 0 &&
       last_layer_bounds == current_layer_bounds &&
       last_layer_content_bounds == current_layer_content_bounds &&
       last_layer_contents_scale == current_layer_contents_scale) {
     time_delta = current_frame_time - last_impl_frame_time_;
   }
 
@@ skipping 133 matching lines @@
     // and recreated, then that picture pile ref could exist indefinitely.  To
     // prevent this, ask the client to update the pile to its own ref.  This
     // will cause PicturePileImpls and their clones to get deleted once the
     // corresponding PictureLayerImpl and any in flight raster jobs go out of
     // scope.
     client_->UpdatePile(it->second);
   }
 }
 
 }  // namespace cc