WIP - compositor worker mega patch.

cc/layers/layer.cc

 // Copyright 2010 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/layers/layer.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 847 matching lines @@
   if (clip_children_->empty())
     clip_children_ = nullptr;
   SetNeedsCommit();
 }
 
 void Layer::SetScrollOffset(const gfx::ScrollOffset& scroll_offset) {
   DCHECK(IsPropertyChangeAllowed());
 
   if (scroll_offset_ == scroll_offset)
     return;
+
+  TRACE_EVENT2("compositor-worker", "Layer::SetScrollOffset", "x",
+               scroll_offset.x(), "y", scroll_offset.y());
+
   scroll_offset_ = scroll_offset;
 
   if (!layer_tree_host_)
     return;
 
   if (TransformNode* transform_node =
           layer_tree_host_->property_trees()->transform_tree.Node(
               transform_tree_index())) {
     if (transform_node->owner_id == id()) {
       transform_node->data.scroll_offset = CurrentScrollOffset();
@@ skipping 1141 matching lines @@
       this, layer_tree_host_->property_trees()->transform_tree);
 }
 
 gfx::Transform Layer::screen_space_transform() const {
   DCHECK_NE(transform_tree_index_, -1);
   return ScreenSpaceTransformFromPropertyTrees(
       this, layer_tree_host_->property_trees()->transform_tree);
 }
 
 }  // namespace cc