aura: Defer OutputSurface creation until widget is available

ui/compositor/compositor.cc

 // Copyright (c) 2012 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 "ui/compositor/compositor.h"
 
 #include <algorithm>
 #include <deque>
 
 #include "base/bind.h"
@@ skipping 50 matching lines @@
     return;
   compositor_->UnlockCompositor();
   compositor_ = NULL;
 }
 
 Compositor::Compositor(ui::ContextFactory* context_factory,
                        scoped_refptr<base::SingleThreadTaskRunner> task_runner)
     : context_factory_(context_factory),
       root_layer_(NULL),
       widget_(gfx::kNullAcceleratedWidget),
+      widget_valid_(false),
+      output_surface_requested_(false),
       surface_id_allocator_(context_factory->CreateSurfaceIdAllocator()),
       task_runner_(task_runner),
       vsync_manager_(new CompositorVSyncManager()),
       device_scale_factor_(0.0f),
       last_started_frame_(0),
       last_ended_frame_(0),
       locks_will_time_out_(true),
       compositor_lock_(NULL),
       layer_animator_collection_(this),
       weak_ptr_factory_(this) {
@@ skipping 87 matching lines @@
   params.gpu_memory_buffer_manager =
       context_factory_->GetGpuMemoryBufferManager();
   params.task_graph_runner = context_factory_->GetTaskGraphRunner();
   params.settings = &settings;
   params.main_task_runner = task_runner_;
   host_ = cc::LayerTreeHost::CreateSingleThreaded(this, &params);
   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();
 }
 
 Compositor::~Compositor() {
   TRACE_EVENT0("shutdown", "Compositor::destructor");
 
   CancelCompositorLock();
   DCHECK(!compositor_lock_);
 
   FOR_EACH_OBSERVER(CompositorObserver, observer_list_,
                     OnCompositingShuttingDown(this));
 
   FOR_EACH_OBSERVER(CompositorAnimationObserver, animation_observer_list_,
                     OnCompositingShuttingDown(this));
 
   DCHECK(begin_frame_observer_list_.empty());
 
   if (root_layer_)
     root_layer_->ResetCompositor();
 
   // Stop all outstanding draws before telling the ContextFactory to tear
   // down any contexts that the |host_| may rely upon.
   host_.reset();
 
   context_factory_->RemoveCompositor(this);
 }
 
 void Compositor::SetOutputSurface(
     scoped_ptr<cc::OutputSurface> output_surface) {
+  output_surface_requested_ = false;
   host_->SetOutputSurface(output_surface.Pass());
 }
 
 void Compositor::ScheduleDraw() {
   host_->SetNeedsCommit();
 }
 
 void Compositor::SetRootLayer(Layer* root_layer) {
   if (root_layer_ == root_layer)
     return;
@@ skipping 73 matching lines @@
     const base::TimeDelta& interval) {
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
          cc::switches::kEnableBeginFrameScheduling)) {
     host_->SetAuthoritativeVSyncInterval(interval);
     return;
   }
 
   vsync_manager_->SetAuthoritativeVSyncInterval(interval);
 }
 
-void Compositor::SetAcceleratedWidgetAndStartCompositor(
-    gfx::AcceleratedWidget widget) {
+void Compositor::SetAcceleratedWidget(gfx::AcceleratedWidget widget) {
   // This function should only get called once.
-  DCHECK_EQ(gfx::kNullAcceleratedWidget, widget_);
+  DCHECK(!widget_valid_);
   widget_ = widget;
-  host_->SetLayerTreeHostClientReady();
+  widget_valid_ = true;
+  if (output_surface_requested_)
+    context_factory_->CreateOutputSurface(weak_ptr_factory_.GetWeakPtr());
+}
+
+gfx::AcceleratedWidget Compositor::widget() const {
+  DCHECK(widget_valid_);
+  return widget_;
 }
 
 scoped_refptr<CompositorVSyncManager> Compositor::vsync_manager() const {
   return vsync_manager_;
 }
 
 void Compositor::AddObserver(CompositorObserver* observer) {
   observer_list_.AddObserver(observer);
 }
 
@@ skipping 64 matching lines @@
     SendDamagedRectsRecursive(child);
 }
 
 void Compositor::Layout() {
   if (!root_layer())
     return;
   SendDamagedRectsRecursive(root_layer());
 }
 
 void Compositor::RequestNewOutputSurface() {
-  context_factory_->CreateOutputSurface(weak_ptr_factory_.GetWeakPtr());
+  DCHECK(!output_surface_requested_);
+  output_surface_requested_ = true;
+  if (widget_valid_)
+    context_factory_->CreateOutputSurface(weak_ptr_factory_.GetWeakPtr());
 }
 
 void Compositor::DidInitializeOutputSurface() {
 }
 
 void Compositor::DidFailToInitializeOutputSurface() {
   // The OutputSurface should already be bound/initialized before being given to
   // the Compositor.
   NOTREACHED();
 }
@@ skipping 65 matching lines @@
                     observer_list_,
                     OnCompositingLockStateChanged(this));
 }
 
 void Compositor::CancelCompositorLock() {
   if (compositor_lock_)
     compositor_lock_->CancelLock();
 }
 
 }  // namespace ui