Remove cc::LayerTreeHostImpl::IsContextLost

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 <limits>
 
 #include "base/basictypes.h"
@@ skipping 239 matching lines @@
       zero_budget_(false),
       device_scale_factor_(1.f),
       overhang_ui_resource_id_(0),
       overdraw_bottom_height_(0.f),
       resourceless_software_draw_(false),
       begin_impl_frame_interval_(BeginFrameArgs::DefaultInterval()),
       animation_registrar_(AnimationRegistrar::Create()),
       rendering_stats_instrumentation_(rendering_stats_instrumentation),
       micro_benchmark_controller_(this),
       need_to_update_visible_tiles_before_draw_(false),
-      have_valid_output_surface_(false),
       shared_bitmap_manager_(manager),
       id_(id),
       transfer_buffer_memory_limit_(0u) {
   DCHECK(proxy_->IsImplThread());
   DidVisibilityChange(this, visible_);
   animation_registrar_->set_supports_scroll_animations(
       proxy_->SupportsImplScrolling());
 
   SetDebugState(settings.initial_debug_state);
 
@@ skipping 1338 matching lines @@
   // Once all layers have been drawn, pending texture uploads should no
   // longer block future uploads.
   resource_provider_->MarkPendingUploadsAsNonBlocking();
 }
 
 void LayerTreeHostImpl::FinishAllRendering() {
   if (renderer_)
     renderer_->Finish();
 }
 
-bool LayerTreeHostImpl::IsContextLost() {
-  DCHECK(proxy_->IsImplThread());
-  // To avoid races, rely only on the lost-surface callback.
-  // See crbug.com/392891.
-  return !have_valid_output_surface_;
-}
-
 void LayerTreeHostImpl::SetUseGpuRasterization(bool use_gpu) {
   if (use_gpu == use_gpu_rasterization_)
     return;
 
   use_gpu_rasterization_ = use_gpu;
   ReleaseTreeResources();
 
   // Replace existing tile manager with another one that uses appropriate
   // rasterizer.
   if (tile_manager_) {
@@ skipping 82 matching lines @@
 }
 
 float LayerTreeHostImpl::VerticalAdjust() const {
   if (!active_tree_->InnerViewportContainerLayer())
     return 0;
 
   return active_tree_->InnerViewportContainerLayer()->BoundsDelta().y();
 }
 
 void LayerTreeHostImpl::DidLoseOutputSurface() {
-  if (!have_valid_output_surface_)
-    return;
-  have_valid_output_surface_ = false;
   if (resource_provider_)
     resource_provider_->DidLoseOutputSurface();
   // 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();
 }
 
 bool LayerTreeHostImpl::HaveRootScrollLayer() const {
@@ skipping 350 matching lines @@
   // Note: order is important here.
   renderer_.reset();
   DestroyTileManager();
   resource_provider_.reset();
   output_surface_.reset();
 
   if (!output_surface->BindToClient(this))
     return false;
 
   output_surface_ = output_surface.Pass();
-  have_valid_output_surface_ = true;
   resource_provider_ =
       ResourceProvider::Create(output_surface_.get(),
                                shared_bitmap_manager_,
                                settings_.highp_threshold_min,
                                settings_.use_rgba_4444_textures,
                                settings_.texture_id_allocation_chunk_size,
                                settings_.use_distance_field_text);
 
   if (output_surface_->capabilities().deferred_gl_initialization)
     EnforceZeroBudget(true);
@@ skipping 1300 matching lines @@
 }
 
 void LayerTreeHostImpl::UnregisterPictureLayerImpl(PictureLayerImpl* layer) {
   std::vector<PictureLayerImpl*>::iterator it =
       std::find(picture_layers_.begin(), picture_layers_.end(), layer);
   DCHECK(it != picture_layers_.end());
   picture_layers_.erase(it);
 }
 
 }  // namespace cc