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..e42bc2f39208b76919f02eb7923bdafada30948d
--- /dev/null
+++ b/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.cc
@@ -0,0 +1,43 @@
+// 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(
+    SynchronousCompositorImpl* compositor) : compositor_(compositor) {
+  DCHECK(compositor_);
+}
+
+SynchronousCompositorExternalBeginFrameSource::
+    ~SynchronousCompositorExternalBeginFrameSource() {
+}
+
+void SynchronousCompositorExternalBeginFrameSource::BeginFrame() {
+  DCHECK(CalledOnValidThread());
+  CallOnBeginFrame(cc::BeginFrameArgs::CreateForSynchronousCompositor());
+}
+
+void SynchronousCompositorExternalBeginFrameSource::OnNeedsBeginFramesChange(
+    bool needs_begin_frames) {
+  DCHECK(CalledOnValidThread());
+  if (compositor_->output_surface() && !compositor_->IsInvokingComposite())
+    compositor_->UpdateContinuousInvalidate();
+}
+
+// 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