Add compositor support for the LatencyInfo.

cc/trees/layer_tree_host_impl.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_impl.h"
 
 #include <algorithm>
 
 #include "base/basictypes.h"
 #include "base/debug/trace_event.h"
@@ skipping 857 matching lines @@
     device_viewport_damage_rect.Union(viewport_damage_rect_);
     viewport_damage_rect_ = gfx::Rect();
 
     active_tree_->root_layer()->render_surface()->damage_tracker()->
         AddDamageNextUpdate(device_viewport_damage_rect);
   }
 
   if (!CalculateRenderPasses(frame))
     return false;
 
+  frame->latency_info = active_tree_->GetLatencyInfo();
+
   // If we return true, then we expect DrawLayers() to be called before this
   // function is called again.
   return true;
 }
 
 void LayerTreeHostImpl::EnforceManagedMemoryPolicy(
     const ManagedMemoryPolicy& policy) {
   bool evicted_resources = client_->ReduceContentsTextureMemoryOnImplThread(
       visible_ ? policy.bytes_limit_when_visible
                : policy.bytes_limit_when_not_visible,
@@ skipping 124 matching lines @@
         gfx::Vector2dF(0.f, top_controls_manager_->controls_top_offset());
     metadata.location_bar_content_translation =
         gfx::Vector2dF(0.f, top_controls_manager_->content_top_offset());
     metadata.overdraw_bottom_height = overdraw_bottom_height_;
   }
 
   if (!RootScrollLayer())
     return metadata;
 
   metadata.root_scroll_offset = RootScrollLayer()->TotalScrollOffset();
+  metadata.latency_info = active_tree_->GetLatencyInfo();
 
   return metadata;
 }
 
 bool LayerTreeHostImpl::AllowPartialSwap() const {
   // We don't track damage on the HUD layer (it interacts with damage tracking
   // visualizations), so disable partial swaps to make the HUD layer display
   // properly.
   return !debug_state_.ShowHudRects();
 }
@@ skipping 79 matching lines @@
   return renderer_ && renderer_->IsContextLost();
 }
 
 const RendererCapabilities& LayerTreeHostImpl::GetRendererCapabilities() const {
   return renderer_->Capabilities();
 }
 
 bool LayerTreeHostImpl::SwapBuffers(const LayerTreeHostImpl::FrameData& frame) {
   if (frame.has_no_damage)
     return false;
-  return renderer_->SwapBuffers();
+  bool result = renderer_->SwapBuffers(frame.latency_info);
+  active_tree_->ClearLatencyInfo();

[jamesr, 2013/04/19 01:25:38]

do we want to clear the latency info if the swap failed?

actually, can this actually fail? why's it a bool?

+  return result;
 }
 
 void LayerTreeHostImpl::EnableVSyncNotification(bool enable) {
   if (output_surface_)
     output_surface_->EnableVSyncNotification(enable);
 }
 
 gfx::Size LayerTreeHostImpl::DeviceViewportSize() const {
   return device_viewport_size();
 }
@@ skipping 963 matching lines @@
 }
 
 void LayerTreeHostImpl::SetDebugState(const LayerTreeDebugState& debug_state) {
   if (debug_state_.continuous_painting != debug_state.continuous_painting)
     paint_time_counter_->ClearHistory();
 
   debug_state_ = debug_state;
 }
 
 }  // namespace cc