Add main thread scrolling reasons to GraphicsLayer::layerTreeAsJSON.

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 852 matching lines @@
 
 void Layer::AddMainThreadScrollingReasons(
     uint32_t main_thread_scrolling_reasons) {
   DCHECK(IsPropertyChangeAllowed());
   DCHECK(main_thread_scrolling_reasons);
   uint32_t new_reasons =
       inputs_.main_thread_scrolling_reasons | main_thread_scrolling_reasons;
   if (inputs_.main_thread_scrolling_reasons == new_reasons)
     return;
   inputs_.main_thread_scrolling_reasons = new_reasons;
+  didUpdateMainThreadScrollingReasons();
   SetNeedsCommit();
 }
 
 void Layer::ClearMainThreadScrollingReasons(
     uint32_t main_thread_scrolling_reasons_to_clear) {
   DCHECK(IsPropertyChangeAllowed());
   DCHECK(main_thread_scrolling_reasons_to_clear);
   uint32_t new_reasons = ~main_thread_scrolling_reasons_to_clear &
                          inputs_.main_thread_scrolling_reasons;
   if (new_reasons == inputs_.main_thread_scrolling_reasons)
     return;
   inputs_.main_thread_scrolling_reasons = new_reasons;
+  didUpdateMainThreadScrollingReasons();
   SetNeedsCommit();
 }
 
 void Layer::SetNonFastScrollableRegion(const Region& region) {
   DCHECK(IsPropertyChangeAllowed());
   if (inputs_.non_fast_scrollable_region == region)
     return;
   inputs_.non_fast_scrollable_region = region;
   SetNeedsCommit();
 }
@@ skipping 677 matching lines @@
 }
 
 std::unique_ptr<base::trace_event::ConvertableToTraceFormat>
 Layer::TakeDebugInfo() {
   if (inputs_.client)
     return inputs_.client->TakeDebugInfo(this);
   else
     return nullptr;
 }
 
+void Layer::didUpdateMainThreadScrollingReasons() {
+  if (inputs_.client)
+    inputs_.client->didUpdateMainThreadScrollingReasons();
+}
+
 void Layer::SetSubtreePropertyChanged() {
   if (subtree_property_changed_)
     return;
   subtree_property_changed_ = true;
   SetNeedsPushProperties();
 }
 
 void Layer::SetLayerPropertyChanged() {
   if (layer_property_changed_)
     return;
@@ skipping 244 matching lines @@
       ->num_copy_requests_in_subtree;
 }
 
 gfx::Transform Layer::screen_space_transform() const {
   DCHECK_NE(transform_tree_index_, -1);
   return draw_property_utils::ScreenSpaceTransform(
       this, layer_tree_host_->property_trees()->transform_tree);
 }
 
 }  // namespace cc