Hook up ui::Compositor to Display's BeginFrameSource

cc/trees/single_thread_proxy.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/single_thread_proxy.h"
 
 #include "base/auto_reset.h"
 #include "base/memory/ptr_util.h"
 #include "base/profiler/scoped_tracker.h"
 #include "base/trace_event/trace_event.h"
@@ skipping 55 matching lines @@
     SchedulerSettings scheduler_settings(
         layer_tree_host_->settings().ToSchedulerSettings());
     scheduler_settings.commit_to_active_tree = CommitToActiveTree();
 
     std::unique_ptr<CompositorTimingHistory> compositor_timing_history(
         new CompositorTimingHistory(
             scheduler_settings.using_synchronous_renderer_compositor,
             CompositorTimingHistory::BROWSER_UMA,
             layer_tree_host_->rendering_stats_instrumentation()));
 
-    BeginFrameSource* frame_source = external_begin_frame_source_.get();
-    if (!scheduler_settings.throttle_frame_production) {
-      // Unthrottled source takes precedence over external sources.
-      unthrottled_begin_frame_source_.reset(new BackToBackBeginFrameSource(
-          task_runner_provider_->MainThreadTaskRunner()));
-      frame_source = unthrottled_begin_frame_source_.get();
-    }
-    if (!frame_source) {
-      synthetic_begin_frame_source_.reset(new SyntheticBeginFrameSource(
-          task_runner_provider_->MainThreadTaskRunner(),
-          BeginFrameArgs::DefaultInterval()));
-      frame_source = synthetic_begin_frame_source_.get();
+    BeginFrameSource* frame_source = nullptr;
+    if (!layer_tree_host_->settings().use_output_surface_begin_frame_source) {
+      frame_source = external_begin_frame_source_.get();
+      if (!scheduler_settings.throttle_frame_production) {
+        // Unthrottled source takes precedence over external sources.
+        unthrottled_begin_frame_source_.reset(new BackToBackBeginFrameSource(
+            task_runner_provider_->MainThreadTaskRunner()));
+        frame_source = unthrottled_begin_frame_source_.get();
+      }
+      if (!frame_source) {
+        synthetic_begin_frame_source_.reset(new SyntheticBeginFrameSource(
+            task_runner_provider_->MainThreadTaskRunner(),
+            BeginFrameArgs::DefaultInterval()));
+        frame_source = synthetic_begin_frame_source_.get();
+      }
     }
 
     scheduler_on_impl_thread_ =
         Scheduler::Create(this, scheduler_settings, layer_tree_host_->id(),
                           task_runner_provider_->MainThreadTaskRunner(),
                           frame_source, std::move(compositor_timing_history));
   }
 
   layer_tree_host_impl_ = layer_tree_host_->CreateLayerTreeHostImpl(this);
 }
@@ skipping 386 matching lines @@
     // TODO(brianderson): We should not be receiving 0 intervals.
     interval = BeginFrameArgs::DefaultInterval();
   }
 
   last_vsync_timebase_ = timebase;
 
   if (synthetic_begin_frame_source_)
     synthetic_begin_frame_source_->OnUpdateVSyncParameters(timebase, interval);
 }
 
+void SingleThreadProxy::SetBeginFrameSource(BeginFrameSource* source) {
+  DCHECK(layer_tree_host_->settings().single_thread_proxy_scheduler);
+  // TODO(enne): this overrides any preexisting begin frame source.  Those
+  // other sources will eventually be removed and this will be the only path.
+  if (!layer_tree_host_->settings().use_output_surface_begin_frame_source)
+    return;
+  if (scheduler_on_impl_thread_)
+    scheduler_on_impl_thread_->SetBeginFrameSource(source);
+}
+
 void SingleThreadProxy::SetEstimatedParentDrawTime(base::TimeDelta draw_time) {
   if (scheduler_on_impl_thread_)
     scheduler_on_impl_thread_->SetEstimatedParentDrawTime(draw_time);
 }
 
 void SingleThreadProxy::DidSwapBuffersOnImplThread() {
   TRACE_EVENT0("cc", "SingleThreadProxy::DidSwapBuffersOnImplThread");
   if (scheduler_on_impl_thread_)
     scheduler_on_impl_thread_->DidSwapBuffers();
   client_->DidPostSwapBuffers();
@@ skipping 395 matching lines @@
       << "DidFinishImplFrame called while not inside an impl frame!";
   inside_impl_frame_ = false;
 #endif
 }
 
 void SingleThreadProxy::SendBeginFramesToChildren(const BeginFrameArgs& args) {
   layer_tree_host_->SendBeginFramesToChildren(args);
 }
 
 }  // namespace cc