Hoist begin frame sources out of scheduler

cc/test/layer_tree_test.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/test/layer_tree_test.h"
 
 #include "base/command_line.h"
 #include "base/location.h"
 #include "base/single_thread_task_runner.h"
 #include "base/thread_task_runner_handle.h"
@@ skipping 885 matching lines @@
 void LayerTreeTest::RequestNewOutputSurface() {
   SetOutputSurfaceOnLayerTreeHost(CreateOutputSurface());
 }
 
 scoped_ptr<OutputSurface> LayerTreeTest::CreateOutputSurface() {
   scoped_ptr<FakeOutputSurface> output_surface = CreateFakeOutputSurface();
   DCHECK_EQ(delegating_renderer_,
             output_surface->capabilities().delegated_rendering);
   output_surface_ = output_surface.get();
 
-  if (settings_.use_external_begin_frame_source) {
+  if (settings_.use_external_begin_frame_source &&
+      settings_.wait_for_beginframe_interval) {
     DCHECK(external_begin_frame_source_);
     DCHECK(external_begin_frame_source_->is_ready());
   }
   return std::move(output_surface);
 }
 
 scoped_ptr<FakeOutputSurface> LayerTreeTest::CreateFakeOutputSurface() {
   if (delegating_renderer_)
     return FakeOutputSurface::CreateDelegating3d();
   else
@@ skipping 104 matching lines @@
 
 RemoteChannelImplForTest* LayerTreeTest::GetRemoteChannelImplForTest() const {
   DCHECK(IsRemoteTest());
   DCHECK(remote_client_layer_tree_host_);
 
   return static_cast<RemoteChannelImplForTest*>(
       remote_client_layer_tree_host_->proxy());
 }
 
 }  // namespace cc