Move context-related callbacks into OutputSurface

cc/trees/layer_tree_host_impl.cc

 // Copyright 2011 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 "cc/trees/layer_tree_host_impl.h"
 
 #include <algorithm>
 
 #include "base/basictypes.h"
 #include "base/debug/trace_event.h"
@@ skipping 1129 matching lines @@
       top_controls_manager_ ? top_controls_manager_->content_top_offset() : 0.f;
   return gfx::SizeF(dip_size.width(),
                     dip_size.height() - top_offset - overdraw_bottom_height_);
 }
 
 const LayerTreeSettings& LayerTreeHostImpl::Settings() const {
   return settings();
 }
 
 void LayerTreeHostImpl::DidLoseOutputSurface() {
-  client_->DidLoseOutputSurfaceOnImplThread();
+  // TODO(jamesr): The renderer_ check is needed to make some of the
+  // LayerTreeHostContextTest tests pass, but shouldn't be necessary (or
+  // important) in production. We should adjust the test to not need this.
+  if (renderer_)
+    client_->DidLoseOutputSurfaceOnImplThread();
 }
 
 void LayerTreeHostImpl::OnSwapBuffersComplete() {
   client_->OnSwapBuffersCompleteOnImplThread();
 }
 
 void LayerTreeHostImpl::Readback(void* pixels,
                                  gfx::Rect rect_in_device_viewport) {
   DCHECK(renderer_);
   renderer_->GetFramebufferPixels(pixels, rect_in_device_viewport);
@@ skipping 925 matching lines @@
 }
 
 void LayerTreeHostImpl::SetDebugState(const LayerTreeDebugState& debug_state) {
   if (debug_state_.continuous_painting != debug_state.continuous_painting)
     paint_time_counter_->ClearHistory();
 
   debug_state_ = debug_state;
 }
 
 }  // namespace cc