Allow layers to signal that additional sequences are needed before surface destruction

ui/compositor/compositor.cc

Index: ui/compositor/compositor.cc
diff --git a/ui/compositor/compositor.cc b/ui/compositor/compositor.cc
index 345d7211872ca4eefbe72fff6caf5d14a3fc5260..cc44cec3679e735e9710dc4f5f9e2a8ac78365e0 100644
--- a/ui/compositor/compositor.cc
+++ b/ui/compositor/compositor.cc
@@ -63,29 +63,6 @@ void CompositorLock::CancelLock() {
   compositor_ = NULL;
 }
 
-}  // namespace ui
-
-namespace {}  // namespace
-
-namespace ui {
-
-class SatisfySwapPromise : public cc::SwapPromise {
- public:
-  explicit SatisfySwapPromise(uint32_t id) : id_(id) {}
-
- private:
-  void DidSwap(cc::CompositorFrameMetadata* metadata) override {
-    metadata->satisfies_sequences.push_back(id_);
-  }
-
-  void DidNotSwap(DidNotSwapReason reason) override {
-    // TODO(jbauman): Send to the SurfaceManager immediately.
-    DCHECK(false);
-  }
-  int64 TraceId() const override { return 0; }
-  uint32_t id_;
-};
-
 Compositor::Compositor(gfx::AcceleratedWidget widget,
                        ui::ContextFactory* context_factory,
                        scoped_refptr<base::SingleThreadTaskRunner> task_runner)
@@ -93,7 +70,6 @@ Compositor::Compositor(gfx::AcceleratedWidget widget,
       root_layer_(NULL),
       widget_(widget),
       surface_id_allocator_(context_factory->CreateSurfaceIdAllocator()),
-      surface_sequence_number_(0),
       compositor_thread_loop_(context_factory->GetCompositorMessageLoop()),
       task_runner_(task_runner),
       vsync_manager_(new CompositorVSyncManager()),
@@ -181,6 +157,7 @@ Compositor::Compositor(gfx::AcceleratedWidget widget,
   UMA_HISTOGRAM_TIMES("GPU.CreateBrowserCompositor",
                       base::TimeTicks::Now() - before_create);
   host_->SetRootLayer(root_web_layer_);
+  host_->set_surface_id_namespace(surface_id_allocator_->id_namespace());
   host_->SetLayerTreeHostClientReady();
 }
 
@@ -436,16 +413,6 @@ void Compositor::SetLayerTreeDebugState(
   host_->SetDebugState(debug_state);
 }
 
-cc::SurfaceSequence Compositor::InsertSurfaceSequenceForNextFrame() {
-  cc::SurfaceSequence sequence;
-  sequence.id_namespace = surface_id_allocator_->id_namespace();
-  sequence.sequence = ++surface_sequence_number_;
-  scoped_ptr<cc::SwapPromise> promise(
-      new SatisfySwapPromise(surface_sequence_number_));
-  host_->QueueSwapPromise(promise.Pass());
-  return sequence;
-}
-
 scoped_refptr<CompositorLock> Compositor::GetCompositorLock() {
   if (!compositor_lock_) {
     compositor_lock_ = new CompositorLock(this);