[cc] Pass on BeginFrameAcks from CompositorEBFS through RWHVAura, DFH.

content/browser/renderer_host/delegated_frame_host.cc

 // Copyright 2014 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 "content/browser/renderer_host/delegated_frame_host.h"
 
 #include <algorithm>
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 813 matching lines @@
 void DelegatedFrameHost::UnlockResources() {
   DCHECK(local_surface_id_.is_valid());
   delegated_frame_evictor_->UnlockFrame();
 }
 
 void DelegatedFrameHost::OnNeedsBeginFrames(bool needs_begin_frames) {
   needs_begin_frame_ = needs_begin_frames;
   support_->SetNeedsBeginFrame(needs_begin_frames);
 }
 
-void DelegatedFrameHost::OnDidFinishFrame(const cc::BeginFrameAck& ack) {}
+void DelegatedFrameHost::OnDidFinishFrame(const cc::BeginFrameAck& ack) {
+  if (ack.source_id != latest_confirmed_begin_frame_source_id_) {
+    // Source changed, we don't know our freshness anymore.
+    latest_confirmed_begin_frame_sequence_number_ =
+        cc::BeginFrameArgs::kInvalidFrameNumber;
+  }
+
+  cc::BeginFrameAck modified_ack = ack;
+  if (skipped_frames_) {
+    // If we skipped the last frame(s), we didn't incorporate the last
+    // CompositorFrame's damage, so need to wait for the next one before
+    // confirming newer sequence numbers.
+    modified_ack.has_damage = false;
+    modified_ack.latest_confirmed_sequence_number =
+        latest_confirmed_begin_frame_sequence_number_;
+  } else {
+    latest_confirmed_begin_frame_source_id_ = modified_ack.source_id;
+    latest_confirmed_begin_frame_sequence_number_ =
+        modified_ack.latest_confirmed_sequence_number;
+  }
+
+  // TODO(eseckler): The interface to CompositorFrameSinkSupport should use
+  // SubmitCompositorFrame and BeginFrameDidNotSwap instead of DidFinishFrame.
+  support_->DidFinishFrame(modified_ack);
+}
 
 void DelegatedFrameHost::CreateCompositorFrameSinkSupport() {
   DCHECK(!support_);
   ImageTransportFactory* factory = ImageTransportFactory::GetInstance();
   support_ = base::MakeUnique<cc::CompositorFrameSinkSupport>(
       this, factory->GetContextFactoryPrivate()->GetSurfaceManager(),
       frame_sink_id_, false /* is_root */,
       false /* handles_frame_sink_id_invalidation */,
       true /* needs_sync_points */);
   if (compositor_)
     compositor_->AddFrameSink(frame_sink_id_);
   if (needs_begin_frame_)
     support_->SetNeedsBeginFrame(true);
 }
 
 void DelegatedFrameHost::ResetCompositorFrameSinkSupport() {
   if (!support_)
     return;
   if (compositor_)
     compositor_->RemoveFrameSink(frame_sink_id_);
   support_.reset();
 }
 
 }  // namespace content