// Copyright (c) 2013 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 "content/renderer/gpu/render_widget_compositor.h" #include #include #if defined(OS_ANDROID) #include "base/android/sys_utils.h" #endif #include "base/command_line.h" #include "base/logging.h" #include "base/strings/string_number_conversions.h" #include "base/synchronization/lock.h" #include "base/time/time.h" #include "base/values.h" #include "cc/base/latency_info_swap_promise.h" #include "cc/base/latency_info_swap_promise_monitor.h" #include "cc/base/switches.h" #include "cc/debug/layer_tree_debug_state.h" #include "cc/debug/micro_benchmark.h" #include "cc/layers/layer.h" #include "cc/output/copy_output_request.h" #include "cc/output/copy_output_result.h" #include "cc/resources/single_release_callback.h" #include "cc/trees/layer_tree_host.h" #include "content/child/child_shared_bitmap_manager.h" #include "content/common/content_switches_internal.h" #include "content/common/gpu/client/context_provider_command_buffer.h" #include "content/public/common/content_switches.h" #include "content/renderer/input/input_handler_manager.h" #include "content/renderer/render_thread_impl.h" #include "gpu/command_buffer/client/gles2_interface.h" #include "third_party/WebKit/public/platform/WebCompositeAndReadbackAsyncCallback.h" #include "third_party/WebKit/public/platform/WebSize.h" #include "third_party/WebKit/public/web/WebWidget.h" #include "ui/gfx/frame_time.h" #include "ui/gl/gl_switches.h" #include "ui/native_theme/native_theme_switches.h" #include "webkit/renderer/compositor_bindings/web_layer_impl.h" namespace base { class Value; } namespace cc { class Layer; } using blink::WebFloatPoint; using blink::WebSize; using blink::WebRect; namespace content { namespace { bool GetSwitchValueAsInt( const CommandLine& command_line, const std::string& switch_string, int min_value, int max_value, int* result) { std::string string_value = command_line.GetSwitchValueASCII(switch_string); int int_value; if (base::StringToInt(string_value, &int_value) && int_value >= min_value && int_value <= max_value) { *result = int_value; return true; } else { LOG(WARNING) << "Failed to parse switch " << switch_string << ": " << string_value; return false; } } } // namespace // static scoped_ptr RenderWidgetCompositor::Create( RenderWidget* widget, bool threaded) { scoped_ptr compositor( new RenderWidgetCompositor(widget, threaded)); CommandLine* cmd = CommandLine::ForCurrentProcess(); cc::LayerTreeSettings settings; // For web contents, layer transforms should scale up the contents of layers // to keep content always crisp when possible. settings.layer_transforms_should_scale_layer_contents = true; settings.throttle_frame_production = !cmd->HasSwitch(switches::kDisableGpuVsync); settings.begin_frame_scheduling_enabled = cmd->HasSwitch(switches::kEnableBeginFrameScheduling); settings.main_frame_before_activation_enabled = cmd->HasSwitch(cc::switches::kEnableMainFrameBeforeActivation) && !cmd->HasSwitch(cc::switches::kDisableMainFrameBeforeActivation); settings.main_frame_before_draw_enabled = !cmd->HasSwitch(cc::switches::kDisableMainFrameBeforeDraw); settings.using_synchronous_renderer_compositor = widget->UsingSynchronousRendererCompositor(); settings.report_overscroll_only_for_scrollable_axes = !widget->UsingSynchronousRendererCompositor(); settings.accelerated_animation_enabled = !cmd->HasSwitch(cc::switches::kDisableThreadedAnimation); settings.touch_hit_testing = !cmd->HasSwitch(cc::switches::kDisableCompositorTouchHitTesting); int default_tile_width = settings.default_tile_size.width(); if (cmd->HasSwitch(switches::kDefaultTileWidth)) { GetSwitchValueAsInt(*cmd, switches::kDefaultTileWidth, 1, std::numeric_limits::max(), &default_tile_width); } int default_tile_height = settings.default_tile_size.height(); if (cmd->HasSwitch(switches::kDefaultTileHeight)) { GetSwitchValueAsInt(*cmd, switches::kDefaultTileHeight, 1, std::numeric_limits::max(), &default_tile_height); } settings.default_tile_size = gfx::Size(default_tile_width, default_tile_height); int max_untiled_layer_width = settings.max_untiled_layer_size.width(); if (cmd->HasSwitch(switches::kMaxUntiledLayerWidth)) { GetSwitchValueAsInt(*cmd, switches::kMaxUntiledLayerWidth, 1, std::numeric_limits::max(), &max_untiled_layer_width); } int max_untiled_layer_height = settings.max_untiled_layer_size.height(); if (cmd->HasSwitch(switches::kMaxUntiledLayerHeight)) { GetSwitchValueAsInt(*cmd, switches::kMaxUntiledLayerHeight, 1, std::numeric_limits::max(), &max_untiled_layer_height); } settings.max_untiled_layer_size = gfx::Size(max_untiled_layer_width, max_untiled_layer_height); RenderThreadImpl* render_thread = RenderThreadImpl::current(); // render_thread may be NULL in tests. if (render_thread) { settings.impl_side_painting = render_thread->is_impl_side_painting_enabled(); settings.gpu_rasterization_forced = render_thread->is_gpu_rasterization_forced(); settings.gpu_rasterization_enabled = render_thread->is_gpu_rasterization_enabled(); settings.create_low_res_tiling = render_thread->is_low_res_tiling_enabled(); settings.can_use_lcd_text = render_thread->is_lcd_text_enabled(); settings.use_distance_field_text = render_thread->is_distance_field_text_enabled(); settings.use_zero_copy = render_thread->is_zero_copy_enabled(); settings.use_one_copy = render_thread->is_one_copy_enabled(); } if (cmd->HasSwitch(switches::kEnableBleedingEdgeRenderingFastPaths)) { settings.recording_mode = cc::LayerTreeSettings::RecordWithSkRecord; } settings.calculate_top_controls_position = cmd->HasSwitch(cc::switches::kEnableTopControlsPositionCalculation); if (cmd->HasSwitch(cc::switches::kTopControlsHeight)) { std::string controls_height_str = cmd->GetSwitchValueASCII(cc::switches::kTopControlsHeight); double controls_height; if (base::StringToDouble(controls_height_str, &controls_height) && controls_height > 0) settings.top_controls_height = controls_height; } if (settings.calculate_top_controls_position && settings.top_controls_height <= 0) { DCHECK(false) << "Top controls repositioning enabled without valid height set."; settings.calculate_top_controls_position = false; } if (cmd->HasSwitch(cc::switches::kTopControlsShowThreshold)) { std::string top_threshold_str = cmd->GetSwitchValueASCII(cc::switches::kTopControlsShowThreshold); double show_threshold; if (base::StringToDouble(top_threshold_str, &show_threshold) && show_threshold >= 0.f && show_threshold <= 1.f) settings.top_controls_show_threshold = show_threshold; } if (cmd->HasSwitch(cc::switches::kTopControlsHideThreshold)) { std::string top_threshold_str = cmd->GetSwitchValueASCII(cc::switches::kTopControlsHideThreshold); double hide_threshold; if (base::StringToDouble(top_threshold_str, &hide_threshold) && hide_threshold >= 0.f && hide_threshold <= 1.f) settings.top_controls_hide_threshold = hide_threshold; } settings.use_pinch_virtual_viewport = cmd->HasSwitch(cc::switches::kEnablePinchVirtualViewport); settings.allow_antialiasing &= !cmd->HasSwitch(cc::switches::kDisableCompositedAntialiasing); // These flags should be mirrored by UI versions in ui/compositor/. settings.initial_debug_state.show_debug_borders = cmd->HasSwitch(cc::switches::kShowCompositedLayerBorders); settings.initial_debug_state.show_fps_counter = cmd->HasSwitch(cc::switches::kShowFPSCounter); settings.initial_debug_state.show_layer_animation_bounds_rects = cmd->HasSwitch(cc::switches::kShowLayerAnimationBounds); settings.initial_debug_state.show_paint_rects = cmd->HasSwitch(switches::kShowPaintRects); settings.initial_debug_state.show_property_changed_rects = cmd->HasSwitch(cc::switches::kShowPropertyChangedRects); settings.initial_debug_state.show_surface_damage_rects = cmd->HasSwitch(cc::switches::kShowSurfaceDamageRects); settings.initial_debug_state.show_screen_space_rects = cmd->HasSwitch(cc::switches::kShowScreenSpaceRects); settings.initial_debug_state.show_replica_screen_space_rects = cmd->HasSwitch(cc::switches::kShowReplicaScreenSpaceRects); settings.initial_debug_state.show_occluding_rects = cmd->HasSwitch(cc::switches::kShowOccludingRects); settings.initial_debug_state.show_non_occluding_rects = cmd->HasSwitch(cc::switches::kShowNonOccludingRects); settings.initial_debug_state.SetRecordRenderingStats( cmd->HasSwitch(cc::switches::kEnableGpuBenchmarking)); if (cmd->HasSwitch(cc::switches::kSlowDownRasterScaleFactor)) { const int kMinSlowDownScaleFactor = 0; const int kMaxSlowDownScaleFactor = INT_MAX; GetSwitchValueAsInt( *cmd, cc::switches::kSlowDownRasterScaleFactor, kMinSlowDownScaleFactor, kMaxSlowDownScaleFactor, &settings.initial_debug_state.slow_down_raster_scale_factor); } if (cmd->HasSwitch(cc::switches::kMaxTilesForInterestArea)) { int max_tiles_for_interest_area; if (GetSwitchValueAsInt(*cmd, cc::switches::kMaxTilesForInterestArea, 1, std::numeric_limits::max(), &max_tiles_for_interest_area)) settings.max_tiles_for_interest_area = max_tiles_for_interest_area; } if (cmd->HasSwitch(cc::switches::kMaxUnusedResourceMemoryUsagePercentage)) { int max_unused_resource_memory_percentage; if (GetSwitchValueAsInt( *cmd, cc::switches::kMaxUnusedResourceMemoryUsagePercentage, 0, 100, &max_unused_resource_memory_percentage)) { settings.max_unused_resource_memory_percentage = max_unused_resource_memory_percentage; } } settings.strict_layer_property_change_checking = cmd->HasSwitch(cc::switches::kStrictLayerPropertyChangeChecking); #if defined(OS_ANDROID) settings.max_partial_texture_updates = 0; if (widget->UsingSynchronousRendererCompositor()) { // Android WebView uses system scrollbars, so make ours invisible. settings.scrollbar_animator = cc::LayerTreeSettings::NoAnimator; settings.solid_color_scrollbar_color = SK_ColorTRANSPARENT; } else { settings.scrollbar_animator = cc::LayerTreeSettings::LinearFade; settings.scrollbar_fade_delay_ms = 300; settings.scrollbar_fade_duration_ms = 300; settings.solid_color_scrollbar_color = SkColorSetARGB(128, 128, 128, 128); } settings.highp_threshold_min = 2048; // Android WebView handles root layer flings itself. settings.ignore_root_layer_flings = widget->UsingSynchronousRendererCompositor(); // RGBA_4444 textures are only enabled for low end devices // and are disabled for Android WebView as it doesn't support the format. settings.use_rgba_4444_textures = base::android::SysUtils::IsLowEndDevice() && !widget->UsingSynchronousRendererCompositor(); if (widget->UsingSynchronousRendererCompositor()) { // TODO(boliu): Set this ratio for Webview. } else if (base::android::SysUtils::IsLowEndDevice()) { // On low-end we want to be very carefull about killing other // apps. So initially we use 50% more memory to avoid flickering // or raster-on-demand. settings.max_memory_for_prepaint_percentage = 67; } else { // On other devices we have increased memory excessively to avoid // raster-on-demand already, so now we reserve 50% _only_ to avoid // raster-on-demand, and use 50% of the memory otherwise. settings.max_memory_for_prepaint_percentage = 50; } // Webview does not own the surface so should not clear it. settings.should_clear_root_render_pass = !widget->UsingSynchronousRendererCompositor(); #elif !defined(OS_MACOSX) if (ui::IsOverlayScrollbarEnabled()) { settings.scrollbar_animator = cc::LayerTreeSettings::Thinning; settings.solid_color_scrollbar_color = SkColorSetARGB(128, 128, 128, 128); } else if (cmd->HasSwitch(cc::switches::kEnablePinchVirtualViewport)) { // use_pinch_zoom_scrollbars is only true on desktop when non-overlay // scrollbars are in use. settings.use_pinch_zoom_scrollbars = true; settings.scrollbar_animator = cc::LayerTreeSettings::LinearFade; settings.solid_color_scrollbar_color = SkColorSetARGB(128, 128, 128, 128); } settings.scrollbar_fade_delay_ms = 500; settings.scrollbar_fade_duration_ms = 300; #endif compositor->Initialize(settings); return compositor.Pass(); } RenderWidgetCompositor::RenderWidgetCompositor(RenderWidget* widget, bool threaded) : threaded_(threaded), suppress_schedule_composite_(false), widget_(widget) { } RenderWidgetCompositor::~RenderWidgetCompositor() {} const base::WeakPtr& RenderWidgetCompositor::GetInputHandler() { return layer_tree_host_->GetInputHandler(); } void RenderWidgetCompositor::SetSuppressScheduleComposite(bool suppress) { if (suppress_schedule_composite_ == suppress) return; if (suppress) TRACE_EVENT_ASYNC_BEGIN0("gpu", "RenderWidgetCompositor::SetSuppressScheduleComposite", this); else TRACE_EVENT_ASYNC_END0("gpu", "RenderWidgetCompositor::SetSuppressScheduleComposite", this); suppress_schedule_composite_ = suppress; } bool RenderWidgetCompositor::BeginMainFrameRequested() const { return layer_tree_host_->BeginMainFrameRequested(); } void RenderWidgetCompositor::UpdateAnimations(base::TimeTicks time) { layer_tree_host_->UpdateClientAnimations(time); } void RenderWidgetCompositor::SetNeedsDisplayOnAllLayers() { layer_tree_host_->SetNeedsDisplayOnAllLayers(); } void RenderWidgetCompositor::SetRasterizeOnlyVisibleContent() { cc::LayerTreeDebugState current = layer_tree_host_->debug_state(); current.rasterize_only_visible_content = true; layer_tree_host_->SetDebugState(current); } void RenderWidgetCompositor::UpdateTopControlsState( cc::TopControlsState constraints, cc::TopControlsState current, bool animate) { layer_tree_host_->UpdateTopControlsState(constraints, current, animate); } void RenderWidgetCompositor::SetOverdrawBottomHeight( float overdraw_bottom_height) { layer_tree_host_->SetOverdrawBottomHeight(overdraw_bottom_height); } void RenderWidgetCompositor::SetNeedsRedrawRect(gfx::Rect damage_rect) { layer_tree_host_->SetNeedsRedrawRect(damage_rect); } void RenderWidgetCompositor::SetNeedsForcedRedraw() { layer_tree_host_->SetNextCommitForcesRedraw(); setNeedsAnimate(); } scoped_ptr RenderWidgetCompositor::CreateLatencyInfoSwapPromiseMonitor( ui::LatencyInfo* latency) { return scoped_ptr( new cc::LatencyInfoSwapPromiseMonitor( latency, layer_tree_host_.get(), NULL)); } int RenderWidgetCompositor::GetLayerTreeId() const { return layer_tree_host_->id(); } void RenderWidgetCompositor::NotifyInputThrottledUntilCommit() { layer_tree_host_->NotifyInputThrottledUntilCommit(); } const cc::Layer* RenderWidgetCompositor::GetRootLayer() const { return layer_tree_host_->root_layer(); } bool RenderWidgetCompositor::ScheduleMicroBenchmark( const std::string& name, scoped_ptr value, const base::Callback)>& callback) { return layer_tree_host_->ScheduleMicroBenchmark(name, value.Pass(), callback); } void RenderWidgetCompositor::Initialize(cc::LayerTreeSettings settings) { scoped_refptr compositor_message_loop_proxy; RenderThreadImpl* render_thread = RenderThreadImpl::current(); cc::SharedBitmapManager* shared_bitmap_manager = NULL; // render_thread may be NULL in tests. if (render_thread) { compositor_message_loop_proxy = render_thread->compositor_message_loop_proxy(); shared_bitmap_manager = render_thread->shared_bitmap_manager(); } if (compositor_message_loop_proxy.get()) { layer_tree_host_ = cc::LayerTreeHost::CreateThreaded( this, shared_bitmap_manager, settings, compositor_message_loop_proxy); } else { layer_tree_host_ = cc::LayerTreeHost::CreateSingleThreaded( this, this, shared_bitmap_manager, settings); } DCHECK(layer_tree_host_); } void RenderWidgetCompositor::setSurfaceReady() { layer_tree_host_->SetLayerTreeHostClientReady(); } void RenderWidgetCompositor::setRootLayer(const blink::WebLayer& layer) { layer_tree_host_->SetRootLayer( static_cast(&layer)->layer()); } void RenderWidgetCompositor::clearRootLayer() { layer_tree_host_->SetRootLayer(scoped_refptr()); } void RenderWidgetCompositor::setViewportSize( const WebSize&, const WebSize& device_viewport_size) { layer_tree_host_->SetViewportSize(device_viewport_size); } WebSize RenderWidgetCompositor::layoutViewportSize() const { return layer_tree_host_->device_viewport_size(); } WebSize RenderWidgetCompositor::deviceViewportSize() const { return layer_tree_host_->device_viewport_size(); } WebFloatPoint RenderWidgetCompositor::adjustEventPointForPinchZoom( const WebFloatPoint& point) const { return point; } void RenderWidgetCompositor::setDeviceScaleFactor(float device_scale) { layer_tree_host_->SetDeviceScaleFactor(device_scale); } float RenderWidgetCompositor::deviceScaleFactor() const { return layer_tree_host_->device_scale_factor(); } void RenderWidgetCompositor::setBackgroundColor(blink::WebColor color) { layer_tree_host_->set_background_color(color); } void RenderWidgetCompositor::setHasTransparentBackground(bool transparent) { layer_tree_host_->set_has_transparent_background(transparent); } void RenderWidgetCompositor::setOverhangBitmap(const SkBitmap& bitmap) { layer_tree_host_->SetOverhangBitmap(bitmap); } void RenderWidgetCompositor::setVisible(bool visible) { layer_tree_host_->SetVisible(visible); } void RenderWidgetCompositor::setPageScaleFactorAndLimits( float page_scale_factor, float minimum, float maximum) { layer_tree_host_->SetPageScaleFactorAndLimits( page_scale_factor, minimum, maximum); } void RenderWidgetCompositor::startPageScaleAnimation( const blink::WebPoint& destination, bool use_anchor, float new_page_scale, double duration_sec) { base::TimeDelta duration = base::TimeDelta::FromMicroseconds( duration_sec * base::Time::kMicrosecondsPerSecond); layer_tree_host_->StartPageScaleAnimation( gfx::Vector2d(destination.x, destination.y), use_anchor, new_page_scale, duration); } void RenderWidgetCompositor::heuristicsForGpuRasterizationUpdated( bool matches_heuristics) { layer_tree_host_->set_has_gpu_rasterization_trigger(matches_heuristics); } void RenderWidgetCompositor::setNeedsAnimate() { layer_tree_host_->SetNeedsAnimate(); } bool RenderWidgetCompositor::commitRequested() const { return layer_tree_host_->CommitRequested(); } void RenderWidgetCompositor::didStopFlinging() { layer_tree_host_->DidStopFlinging(); } void RenderWidgetCompositor::registerForAnimations(blink::WebLayer* layer) { cc::Layer* cc_layer = static_cast(layer)->layer(); cc_layer->layer_animation_controller()->SetAnimationRegistrar( layer_tree_host_->animation_registrar()); } void RenderWidgetCompositor::registerViewportLayers( const blink::WebLayer* pageScaleLayer, const blink::WebLayer* innerViewportScrollLayer, const blink::WebLayer* outerViewportScrollLayer) { layer_tree_host_->RegisterViewportLayers( static_cast(pageScaleLayer)->layer(), static_cast(innerViewportScrollLayer) ->layer(), // The outer viewport layer will only exist when using pinch virtual // viewports. outerViewportScrollLayer ? static_cast( outerViewportScrollLayer)->layer() : NULL); } void RenderWidgetCompositor::clearViewportLayers() { layer_tree_host_->RegisterViewportLayers(scoped_refptr(), scoped_refptr(), scoped_refptr()); } void CompositeAndReadbackAsyncCallback( blink::WebCompositeAndReadbackAsyncCallback* callback, scoped_ptr result) { if (result->HasBitmap()) { scoped_ptr result_bitmap = result->TakeBitmap(); callback->didCompositeAndReadback(*result_bitmap); } else { callback->didCompositeAndReadback(SkBitmap()); } } void RenderWidgetCompositor::compositeAndReadbackAsync( blink::WebCompositeAndReadbackAsyncCallback* callback) { DCHECK(layer_tree_host_->root_layer()); scoped_ptr request = cc::CopyOutputRequest::CreateBitmapRequest( base::Bind(&CompositeAndReadbackAsyncCallback, callback)); layer_tree_host_->root_layer()->RequestCopyOfOutput(request.Pass()); if (!threaded_) { widget_->webwidget()->animate(0.0); widget_->webwidget()->layout(); layer_tree_host_->Composite(gfx::FrameTime::Now()); } } void RenderWidgetCompositor::finishAllRendering() { layer_tree_host_->FinishAllRendering(); } void RenderWidgetCompositor::setDeferCommits(bool defer_commits) { layer_tree_host_->SetDeferCommits(defer_commits); } void RenderWidgetCompositor::setShowFPSCounter(bool show) { cc::LayerTreeDebugState debug_state = layer_tree_host_->debug_state(); debug_state.show_fps_counter = show; layer_tree_host_->SetDebugState(debug_state); } void RenderWidgetCompositor::setShowPaintRects(bool show) { cc::LayerTreeDebugState debug_state = layer_tree_host_->debug_state(); debug_state.show_paint_rects = show; layer_tree_host_->SetDebugState(debug_state); } void RenderWidgetCompositor::setShowDebugBorders(bool show) { cc::LayerTreeDebugState debug_state = layer_tree_host_->debug_state(); debug_state.show_debug_borders = show; layer_tree_host_->SetDebugState(debug_state); } void RenderWidgetCompositor::setContinuousPaintingEnabled(bool enabled) { cc::LayerTreeDebugState debug_state = layer_tree_host_->debug_state(); debug_state.continuous_painting = enabled; layer_tree_host_->SetDebugState(debug_state); } void RenderWidgetCompositor::setShowScrollBottleneckRects(bool show) { cc::LayerTreeDebugState debug_state = layer_tree_host_->debug_state(); debug_state.show_touch_event_handler_rects = show; debug_state.show_wheel_event_handler_rects = show; debug_state.show_non_fast_scrollable_rects = show; layer_tree_host_->SetDebugState(debug_state); } void RenderWidgetCompositor::WillBeginMainFrame(int frame_id) { widget_->InstrumentWillBeginFrame(frame_id); widget_->willBeginCompositorFrame(); } void RenderWidgetCompositor::DidBeginMainFrame() { widget_->InstrumentDidBeginFrame(); } void RenderWidgetCompositor::Animate(base::TimeTicks frame_begin_time) { widget_->webwidget()->animate( (frame_begin_time - base::TimeTicks()).InSecondsF()); } void RenderWidgetCompositor::Layout() { widget_->webwidget()->layout(); } void RenderWidgetCompositor::ApplyScrollAndScale( const gfx::Vector2d& scroll_delta, float page_scale) { widget_->webwidget()->applyScrollAndScale(scroll_delta, page_scale); } scoped_ptr RenderWidgetCompositor::CreateOutputSurface( bool fallback) { return widget_->CreateOutputSurface(fallback); } void RenderWidgetCompositor::DidInitializeOutputSurface() { } void RenderWidgetCompositor::WillCommit() { widget_->InstrumentWillComposite(); } void RenderWidgetCompositor::DidCommit() { widget_->DidCommitCompositorFrame(); widget_->didBecomeReadyForAdditionalInput(); } void RenderWidgetCompositor::DidCommitAndDrawFrame() { widget_->didCommitAndDrawCompositorFrame(); } void RenderWidgetCompositor::DidCompleteSwapBuffers() { widget_->didCompleteSwapBuffers(); if (!threaded_) widget_->OnSwapBuffersComplete(); } void RenderWidgetCompositor::ScheduleComposite() { if (!suppress_schedule_composite_) widget_->scheduleComposite(); } void RenderWidgetCompositor::ScheduleAnimation() { widget_->scheduleAnimation(); } void RenderWidgetCompositor::DidPostSwapBuffers() { widget_->OnSwapBuffersPosted(); } void RenderWidgetCompositor::DidAbortSwapBuffers() { widget_->OnSwapBuffersAborted(); } void RenderWidgetCompositor::RateLimitSharedMainThreadContext() { cc::ContextProvider* provider = RenderThreadImpl::current()->SharedMainThreadContextProvider().get(); provider->ContextGL()->RateLimitOffscreenContextCHROMIUM(); } } // namespace content