cc: Emulate BeginFrame in OutputSurfaces that don't support it natively

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index ae3b2b6f1aa1abe466b5905f3f0c62dcf6506231..0654b581ebdc8c4ac4a9fdfaee9741fa67b1c9c7 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -1044,11 +1044,6 @@ void LayerTreeHostImpl::SetNeedsRedrawRect(gfx::Rect damage_rect) {
   client_->SetNeedsRedrawRectOnImplThread(damage_rect);
 }
 
-void LayerTreeHostImpl::OnVSyncParametersChanged(base::TimeTicks timebase,
-                                                 base::TimeDelta interval) {
-  client_->OnVSyncParametersChanged(timebase, interval);
-}
-
 void LayerTreeHostImpl::BeginFrame(base::TimeTicks frame_time) {
   client_->BeginFrameOnImplThread(frame_time);
 }
@@ -1492,6 +1487,28 @@ bool LayerTreeHostImpl::InitializeRenderer(
     resource_provider_ = resource_provider.Pass();
   }
 
+  // Setup BeginFrameEmulation if it's not supported natively
+  if (!settings_.begin_frame_scheduling_enabled) {
+    const base::TimeDelta display_refresh_interval =
+      base::TimeDelta::FromMicroseconds(
+          base::Time::kMicrosecondsPerSecond /
+          settings_.refresh_rate);
+
+    output_surface->InitializeBeginFrameEmulation(
+        proxy_->ImplThread(),
+        settings_.throttle_frame_production,
+        display_refresh_interval,
+        GetRendererCapabilities().using_swap_complete_callback || true);
+  }
+
+  int max_frames_pending =
+      output_surface->capabilities().max_frames_pending;
+  if (max_frames_pending <= 0)
+    max_frames_pending = FrameRateController::DEFAULT_MAX_FRAMES_PENDING;
+  if (output_surface->capabilities().has_parent_compositor)
+    max_frames_pending = 1;
+  output_surface->SetMaxFramesPending(max_frames_pending);
+
   output_surface_ = output_surface.Pass();
 
   if (!visible_)