Revert of Mojo multiple command buffer support and sample

mojo/services/view_manager/window_tree_host_impl.cc

Index: mojo/services/view_manager/window_tree_host_impl.cc
diff --git a/mojo/services/view_manager/window_tree_host_impl.cc b/mojo/services/view_manager/window_tree_host_impl.cc
index 267bdcaf039613beed5edb21171ed9e31ff32f0b..9f201b0845a6a45905710b4198d6f8791f04d8b0 100644
--- a/mojo/services/view_manager/window_tree_host_impl.cc
+++ b/mojo/services/view_manager/window_tree_host_impl.cc
@@ -67,21 +67,29 @@
 
 WindowTreeHostImpl::WindowTreeHostImpl(
     NativeViewportPtr viewport,
-    GpuPtr gpu_service,
     const gfx::Rect& bounds,
     const Callback<void()>& compositor_created_callback,
     const Callback<void()>& native_viewport_closed_callback,
     const Callback<void(EventPtr)>& event_received_callback)
     : native_viewport_(viewport.Pass()),
-      gpu_service_(gpu_service.Pass()),
-      widget_(gfx::kNullAcceleratedWidget),
       compositor_created_callback_(compositor_created_callback),
       native_viewport_closed_callback_(native_viewport_closed_callback),
       event_received_callback_(event_received_callback),
       bounds_(bounds) {
   native_viewport_.set_client(this);
   native_viewport_->Create(Rect::From(bounds));
-  native_viewport_->Show();
+
+  MessagePipe pipe;
+  native_viewport_->CreateGLES2Context(
+      MakeRequest<CommandBuffer>(pipe.handle0.Pass()));
+
+  // The ContextFactory must exist before any Compositors are created.
+  if (context_factory_) {
+    delete context_factory_;
+    context_factory_ = NULL;
+  }
+  context_factory_ = new ContextFactoryImpl(pipe.handle1.Pass());
+  aura::Env::GetInstance()->set_context_factory(context_factory_);
 
   window()->SetLayoutManager(new RootLayoutManager());
 }
@@ -99,11 +107,13 @@
 }
 
 gfx::AcceleratedWidget WindowTreeHostImpl::GetAcceleratedWidget() {
-  return widget_;
+  NOTIMPLEMENTED() << "GetAcceleratedWidget";
+  return gfx::kNullAcceleratedWidget;
 }
 
 void WindowTreeHostImpl::Show() {
   window()->Show();
+  native_viewport_->Show();
 }
 
 void WindowTreeHostImpl::Hide() {
@@ -158,35 +168,21 @@
 ////////////////////////////////////////////////////////////////////////////////
 // WindowTreeHostImpl, NativeViewportClient implementation:
 
-void WindowTreeHostImpl::OnCreated(uint64_t native_viewport_id) {
-  LOG(ERROR) << "OnCreated " << native_viewport_id;
-  CommandBufferPtr cb;
-  gpu_service_->CreateOnscreenGLES2Context(
-      native_viewport_id, Size::From(bounds_.size()), Get(&cb));
-  widget_ = reinterpret_cast<gfx::AcceleratedWidget>(native_viewport_id);
-
-  // The ContextFactory must exist before any Compositors are created.
-  if (context_factory_) {
-    delete context_factory_;
-    context_factory_ = NULL;
-  }
-  context_factory_ = new ContextFactoryImpl(cb.PassMessagePipe());
-  aura::Env::GetInstance()->set_context_factory(context_factory_);
-
-  CreateCompositor(gfx::kNullAcceleratedWidget);
+void WindowTreeHostImpl::OnCreated() {
+  CreateCompositor(GetAcceleratedWidget());
   compositor_created_callback_.Run();
 }
 
 void WindowTreeHostImpl::OnBoundsChanged(RectPtr bounds) {
   bounds_ = bounds.To<gfx::Rect>();
-  if (context_factory_)
-    OnHostResized(bounds_.size());
+  OnHostResized(bounds_.size());
 }
 
-void WindowTreeHostImpl::OnDestroyed() {
+void WindowTreeHostImpl::OnDestroyed(const mojo::Callback<void()>& callback) {
   DestroyCompositor();
   native_viewport_closed_callback_.Run();
   // TODO(beng): quit the message loop once we are on our own thread.
+  callback.Run();
 }
 
 void WindowTreeHostImpl::OnEvent(EventPtr event,