CC: Force push properties for all layers when tracing is started

cc/trees/layer_tree_host.cc

 // Copyright 2011 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/trees/layer_tree_host.h"
 
 #include <algorithm>
 #include <stack>
 #include <string>
 
 #include "base/atomic_sequence_num.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/stl_util.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "cc/animation/animation_registrar.h"
 #include "cc/animation/layer_animation_controller.h"
 #include "cc/base/math_util.h"
 #include "cc/debug/devtools_instrumentation.h"
+#include "cc/debug/frame_viewer_instrumentation.h"
 #include "cc/debug/rendering_stats_instrumentation.h"
 #include "cc/input/layer_selection_bound.h"
 #include "cc/input/page_scale_animation.h"
 #include "cc/input/top_controls_manager.h"
 #include "cc/layers/heads_up_display_layer.h"
 #include "cc/layers/heads_up_display_layer_impl.h"
 #include "cc/layers/layer.h"
 #include "cc/layers/layer_iterator.h"
 #include "cc/layers/painted_scrollbar_layer.h"
 #include "cc/layers/render_surface.h"
@@ skipping 253 matching lines @@
 
   LayerTreeImpl* sync_tree = host_impl->sync_tree();
 
   if (next_commit_forces_redraw_) {
     sync_tree->ForceRedrawNextActivation();
     next_commit_forces_redraw_ = false;
   }
 
   sync_tree->set_source_frame_number(source_frame_number());
 
+  bool is_new_trace;

[danakj, 2015/03/16 19:06:49]

Can you move this up above the |sync_tree| variable? It's kinda in the middle of
"update the sync tree" here

+  TRACE_EVENT_IS_NEW_TRACE(&is_new_trace);
+  if (is_new_trace &&
+      frame_viewer_instrumentation::IsTracingLayerTreeSnapshots()) {
+    LayerTreeHostCommon::CallFunctionForSubtree(
+        root_layer(), [](Layer* layer) { layer->DidBeginTracing(); });
+  }
+
   if (needs_full_tree_sync_) {
     sync_tree->SetRootLayer(TreeSynchronizer::SynchronizeTrees(
         root_layer(), sync_tree->DetachLayerTree(), sync_tree));
   }
   sync_tree->set_needs_full_tree_sync(needs_full_tree_sync_);
   needs_full_tree_sync_ = false;
 
   if (hud_layer_.get()) {
     LayerImpl* hud_impl = LayerTreeHostCommon::FindLayerInSubtree(
         sync_tree->root_layer(), hud_layer_->id());
@@ skipping 964 matching lines @@
     bool children_need_begin_frames) const {
   proxy_->SetChildrenNeedBeginFrames(children_need_begin_frames);
 }
 
 void LayerTreeHost::SendBeginFramesToChildren(
     const BeginFrameArgs& args) const {
   client_->SendBeginFramesToChildren(args);
 }
 
 }  // namespace cc