cc: Make separate interface for BeginFrame ipc from OutputSurface

content/test/web_layer_tree_view_impl_for_testing.cc

Index: content/test/web_layer_tree_view_impl_for_testing.cc
diff --git a/content/test/web_layer_tree_view_impl_for_testing.cc b/content/test/web_layer_tree_view_impl_for_testing.cc
index 5714a2f950a966e4ac6c3121e2c923661f753d3a..7210193a6216bdb7bf8b0cc5f6d311807a1acf3a 100644
--- a/content/test/web_layer_tree_view_impl_for_testing.cc
+++ b/content/test/web_layer_tree_view_impl_for_testing.cc
@@ -12,6 +12,7 @@
 #include "cc/input/input_handler.h"
 #include "cc/layers/layer.h"
 #include "cc/output/output_surface.h"
+#include "cc/scheduler/begin_frame_source.h"
 #include "cc/test/test_context_provider.h"
 #include "cc/trees/layer_tree_host.h"
 #include "content/test/test_blink_web_unit_test_support.h"
@@ -43,7 +44,12 @@ void WebLayerTreeViewImplForTesting::Initialize() {
   // Accelerated animations are enabled for unit tests.
   settings.accelerated_animation_enabled = true;
   layer_tree_host_ = cc::LayerTreeHost::CreateSingleThreaded(
-      this, this, NULL, settings, base::MessageLoopProxy::current());
+      this,
+      this,
+      NULL,
+      settings,
+      base::MessageLoopProxy::current(),
+      scoped_ptr<cc::ExternalBeginFrameSource>());
   DCHECK(layer_tree_host_);
 }