[cc] Forward BeginFrameAcks through DirectCFS and CFSSupport.

cc/surfaces/compositor_frame_sink_support_unittest.cc

 // Copyright 2017 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/surfaces/compositor_frame_sink_support.h"
 
 #include "base/macros.h"
 #include "cc/output/compositor_frame.h"
 #include "cc/surfaces/compositor_frame_sink_support_client.h"
 #include "cc/surfaces/frame_sink_id.h"
@@ skipping 135 matching lines @@
         true /* handles_frame_sink_id_invalidation */,
         true /* needs_sync_points */));
     supports_.push_back(base::MakeUnique<CompositorFrameSinkSupport>(
         this, &surface_manager_, kChildFrameSink1, false /* is_root */,
         true /* handles_frame_sink_id_invalidation */,
         true /* needs_sync_points */));
     supports_.push_back(base::MakeUnique<CompositorFrameSinkSupport>(
         this, &surface_manager_, kChildFrameSink2, false /* is_root */,
         true /* handles_frame_sink_id_invalidation */,
         true /* needs_sync_points */));
+    surface_manager_.RegisterBeginFrameSource(begin_frame_source_.get(),

[Fady Samuel, 2017/03/01 19:49:07]

I guess cc::Display normally does this? Could you please add a comment about why
this is necessary in this unit test? Thanks!

[Eric Seckler, 2017/03/02 09:41:59]

Correct, normally done by the display. The other thing that seems to be missing
here is registering the hierarchy of the frame sinks (which would assign the BFS
to the other frame sinks). But since it doesn't seem to be required for the
tests, I guess we can leave it out.

Added a comment.

+                                              kDisplayFrameSink);
   }
 
   void TearDown() override {
     surface_manager_.SetDependencyTracker(nullptr);
+    surface_manager_.UnregisterBeginFrameSource(begin_frame_source_.get());
 
     // SurfaceDependencyTracker depends on this BeginFrameSource and so it must
     // be destroyed AFTER the dependency tracker is destroyed.
     begin_frame_source_.reset();
 
     supports_.clear();
   }
 
   // CompositorFrameSinkSupportClient implementation.
   void DidReceiveCompositorFrameAck() override {}
@@ skipping 546 matching lines @@
 
   // Verify that the parent Surface has activated and no longer has a pending
   // CompositorFrame. Also verify that |child_id1| is no longer a child
   // reference of |parent_id|.
   EXPECT_TRUE(parent_surface()->HasActiveFrame());
   EXPECT_FALSE(parent_surface()->HasPendingFrame());
   EXPECT_THAT(parent_surface()->blocking_surfaces_for_testing(), IsEmpty());
   EXPECT_THAT(GetChildReferences(parent_id), UnorderedElementsAre(child_id2));
 }
 
+TEST_F(CompositorFrameSinkSupportTest, PassesOnBeginFrameAcks) {
+  // Request BeginFrames.
+  display_support().SetNeedsBeginFrame(true);
+
+  // Issue a BeginFrame.
+  BeginFrameArgs args =
+      CreateBeginFrameArgsForTesting(BEGINFRAME_FROM_HERE, 0, 1);
+  begin_frame_source()->TestOnBeginFrame(args);
+
+  // Check that the support forwards our ack to the BeginFrameSource.
+  BeginFrameAck ack(0, 1, 1, 0, false);
+  display_support().DidFinishFrame(ack);
+  EXPECT_EQ(ack, begin_frame_source()->LastAckForObserver(&display_support()));
+}
+
 }  // namespace test
 }  // namespace cc