cc: Make separate interface for BeginFrame ipc from OutputSurface

content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc

Index: content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc
diff --git a/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc b/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc
new file mode 100644
index 0000000000000000000000000000000000000000..5437d59588cbed1ba9a3f4865ea1ac3f9ba201af
--- /dev/null
+++ b/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc
@@ -0,0 +1,68 @@
+// 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/android/in_process/synchronous_compositor_external_begin_frame_source.h"
+
+#include "cc/output/begin_frame_args.h"
+#include "content/browser/android/in_process/synchronous_compositor_impl.h"
+#include "content/public/browser/browser_thread.h"
+
+namespace content {
+
+SynchronousCompositorExternalBeginFrameSource::
+    SynchronousCompositorExternalBeginFrameSource(int routing_id)
+    : routing_id_(routing_id),
+      compositor_(nullptr) {
+}
+
+SynchronousCompositorExternalBeginFrameSource::
+    ~SynchronousCompositorExternalBeginFrameSource() {
+  DCHECK(CalledOnValidThread());
+  if (compositor_)
+    compositor_->SetExternalBeginFrameSource(nullptr);
+}
+
+void SynchronousCompositorExternalBeginFrameSource::BeginFrame() {
+  DCHECK(CalledOnValidThread());
+  CallOnBeginFrame(cc::BeginFrameArgs::CreateForSynchronousCompositor());
+}
+
+void SynchronousCompositorExternalBeginFrameSource::SetCompositor(
+    SynchronousCompositorImpl* compositor) {
+  DCHECK(CalledOnValidThread());
+  compositor_ = compositor;
+}
+
+void SynchronousCompositorExternalBeginFrameSource::OnNeedsBeginFramesChange(
+    bool needs_begin_frames) {
+  DCHECK(CalledOnValidThread());
+
+  if (compositor_)
+    compositor_->SetContinuousInvalidate(needs_begin_frames);
+}
+
+void SynchronousCompositorExternalBeginFrameSource::SetClientReady() {
+  DCHECK(CalledOnValidThread());
+
+  SynchronousCompositorImpl* compositor = GetCompositor();

[boliu, 2014/10/30 16:21:32]

Just put the code for GetCompositor here, since this is the only callsite. It's
super confusing to have both compositor_ and GetCompositor that does *not*
return compositor_

[simonhong, 2014/10/31 00:22:08]

Done.

+  if (compositor) {
+    compositor->SetExternalBeginFrameSource(this);
+    SetCompositor(compositor);

[boliu, 2014/10/30 16:21:32]

nit: I think it's awkward SetCompositor is called both here and from
SyncComopsitorImpl. Can you just have it only be called from
SetExternalBeginFrameSource? Kinda sucks to re-enter into this class, but imo
it's more consistent than this.

[simonhong, 2014/10/31 00:22:08]

Done.

+  }
+}
+
+SynchronousCompositorImpl*
+SynchronousCompositorExternalBeginFrameSource::GetCompositor() const {
+  return SynchronousCompositorImpl::FromRoutingID(routing_id_);
+}
+
+// Not using base::NonThreadSafe as we want to enforce a more exacting threading
+// requirement: SynchronousCompositorExternalBeginFrameSource() must only be
+// used on the UI thread.
+bool
+SynchronousCompositorExternalBeginFrameSource::CalledOnValidThread() const {
+  return BrowserThread::CurrentlyOn(BrowserThread::UI);
+}
+
+}  // namespace content