// 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. #ifndef CONTENT_RENDERER_RENDER_THREAD_IMPL_H_ #define CONTENT_RENDERER_RENDER_THREAD_IMPL_H_ #include #include #include #include #include #include #include #include #include "base/cancelable_callback.h" #include "base/macros.h" #include "base/memory/memory_pressure_listener.h" #include "base/memory/ref_counted.h" #include "base/metrics/user_metrics_action.h" #include "base/observer_list.h" #include "base/optional.h" #include "base/strings/string16.h" #include "base/threading/thread_checker.h" #include "base/time/time.h" #include "base/timer/timer.h" #include "build/build_config.h" #include "content/child/child_thread_impl.h" #include "content/common/content_export.h" #include "content/common/frame.mojom.h" #include "content/common/frame_replication_state.h" #include "content/common/frame_sink_provider.mojom.h" #include "content/common/render_frame_message_filter.mojom.h" #include "content/common/render_frame_metadata.mojom.h" #include "content/common/render_message_filter.mojom.h" #include "content/common/renderer.mojom.h" #include "content/common/renderer_host.mojom.h" #include "content/public/renderer/render_thread.h" #include "content/public/renderer/url_loader_throttle_provider.h" #include "content/renderer/gpu/compositor_dependencies.h" #include "content/renderer/layout_test_dependencies.h" #include "content/renderer/media/audio/audio_input_ipc_factory.h" #include "content/renderer/media/audio/audio_output_ipc_factory.h" #include "gpu/ipc/client/gpu_channel_host.h" #include "ipc/ipc_sync_channel.h" #include "media/media_buildflags.h" #include "mojo/public/cpp/bindings/associated_binding.h" #include "mojo/public/cpp/bindings/binding.h" #include "mojo/public/cpp/bindings/thread_safe_interface_ptr.h" #include "net/base/network_change_notifier.h" #include "net/nqe/effective_connection_type.h" #include "services/network/public/mojom/url_loader_factory.mojom.h" #include "services/service_manager/public/cpp/bind_source_info.h" #include "services/service_manager/public/cpp/binder_registry.h" #include "services/viz/public/interfaces/compositing/compositing_mode_watcher.mojom.h" #include "third_party/blink/public/common/associated_interfaces/associated_interface_registry.h" #include "third_party/blink/public/mojom/dom_storage/storage_partition_service.mojom.h" #include "third_party/blink/public/platform/scheduler/web_rail_mode_observer.h" #include "third_party/blink/public/platform/web_connection_type.h" #include "third_party/blink/public/web/web_memory_statistics.h" #include "ui/gfx/native_widget_types.h" #if defined(OS_MACOSX) #include "third_party/blink/public/platform/mac/web_scrollbar_theme.h" #endif class SkBitmap; namespace blink { class WebMediaStreamCenter; } namespace base { class SingleThreadTaskRunner; class Thread; } namespace cc { class BeginFrameSource; class LayerTreeFrameSink; class SyntheticBeginFrameSource; class TaskGraphRunner; } namespace discardable_memory { class ClientDiscardableSharedMemoryManager; } namespace gpu { class GpuChannelHost; } namespace IPC { class MessageFilter; } namespace media { class GpuVideoAcceleratorFactories; } namespace v8 { class Extension; } namespace viz { class BeginFrameSource; class RasterContextProvider; class SyntheticBeginFrameSource; } namespace ws { class ContextProviderCommandBuffer; class Gpu; } // namespace ws namespace content { class AppCacheDispatcher; class AecDumpMessageFilter; class AudioRendererMixerManager; class BrowserPluginManager; class CategorizedWorkerPool; class DomStorageDispatcher; class FrameSwapMessageQueue; class GpuVideoAcceleratorFactoriesImpl; class IndexedDBDispatcher; class LowMemoryModeController; class MidiMessageFilter; class P2PSocketDispatcher; class PeerConnectionDependencyFactory; class PeerConnectionTracker; class RenderThreadObserver; class RendererBlinkPlatformImpl; class ResourceDispatcher; class VideoCaptureImplManager; #if defined(OS_ANDROID) class StreamTextureFactory; #endif #if defined(COMPILER_MSVC) // See explanation for other RenderViewHostImpl which is the same issue. #pragma warning(push) #pragma warning(disable: 4250) #endif // The RenderThreadImpl class represents a background thread where RenderView // instances live. The RenderThread supports an API that is used by its // consumer to talk indirectly to the RenderViews and supporting objects. // Likewise, it provides an API for the RenderViews to talk back to the main // process (i.e., their corresponding WebContentsImpl). // // Most of the communication occurs in the form of IPC messages. They are // routed to the RenderThread according to the routing IDs of the messages. // The routing IDs correspond to RenderView instances. class CONTENT_EXPORT RenderThreadImpl : public RenderThread, public ChildThreadImpl, public blink::scheduler::WebRAILModeObserver, public mojom::Renderer, public viz::mojom::CompositingModeWatcher, public CompositorDependencies { public: static RenderThreadImpl* current(); static mojom::RenderMessageFilter* current_render_message_filter(); static RendererBlinkPlatformImpl* current_blink_platform_impl(); static void SetRenderMessageFilterForTesting( mojom::RenderMessageFilter* render_message_filter); static void SetRendererBlinkPlatformImplForTesting( RendererBlinkPlatformImpl* blink_platform_impl); // Returns the task runner for the main thread where the RenderThread lives. static scoped_refptr DeprecatedGetMainTaskRunner(); RenderThreadImpl( base::RepeatingClosure quit_closure, std::unique_ptr scheduler); RenderThreadImpl( const InProcessChildThreadParams& params, std::unique_ptr scheduler); ~RenderThreadImpl() override; void Shutdown() override; bool ShouldBeDestroyed() override; // When initializing WebKit, ensure that any schemes needed for the content // module are registered properly. Static to allow sharing with tests. static void RegisterSchemes(); // RenderThread implementation: bool Send(IPC::Message* msg) override; IPC::SyncChannel* GetChannel() override; std::string GetLocale() override; IPC::SyncMessageFilter* GetSyncMessageFilter() override; void AddRoute(int32_t routing_id, IPC::Listener* listener) override; void RemoveRoute(int32_t routing_id) override; int GenerateRoutingID() override; void AddFilter(IPC::MessageFilter* filter) override; void RemoveFilter(IPC::MessageFilter* filter) override; void AddObserver(RenderThreadObserver* observer) override; void RemoveObserver(RenderThreadObserver* observer) override; void SetResourceDispatcherDelegate( ResourceDispatcherDelegate* delegate) override; std::unique_ptr HostAllocateSharedMemoryBuffer( size_t buffer_size) override; void RegisterExtension(v8::Extension* extension) override; int PostTaskToAllWebWorkers(const base::Closure& closure) override; bool ResolveProxy(const GURL& url, std::string* proxy_list) override; base::WaitableEvent* GetShutdownEvent() override; int32_t GetClientId() override; bool IsOnline() override; void SetRendererProcessType( blink::scheduler::RendererProcessType type) override; blink::WebString GetUserAgent() const override; // IPC::Listener implementation via ChildThreadImpl: void OnAssociatedInterfaceRequest( const std::string& name, mojo::ScopedInterfaceEndpointHandle handle) override; // ChildThread implementation via ChildThreadImpl: scoped_refptr GetIOTaskRunner() override; // CompositorDependencies implementation. bool IsGpuRasterizationForced() override; int GetGpuRasterizationMSAASampleCount() override; bool IsLcdTextEnabled() override; bool IsZeroCopyEnabled() override; bool IsPartialRasterEnabled() override; bool IsGpuMemoryBufferCompositorResourcesEnabled() override; bool IsElasticOverscrollEnabled() override; bool IsUseZoomForDSFEnabled() override; scoped_refptr GetCompositorMainThreadTaskRunner() override; scoped_refptr GetCompositorImplThreadTaskRunner() override; blink::scheduler::WebThreadScheduler* GetWebMainThreadScheduler() override; cc::TaskGraphRunner* GetTaskGraphRunner() override; bool IsScrollAnimatorEnabled() override; std::unique_ptr CreateUkmRecorderFactory() override; #ifdef OS_ANDROID bool UsingSynchronousCompositing() override; #endif bool IsThreadedAnimationEnabled(); // blink::scheduler::WebRAILModeObserver implementation. void OnRAILModeChanged(v8::RAILMode rail_mode) override; // viz::mojom::CompositingModeWatcher implementation. void CompositingModeFallbackToSoftware() override; // Whether gpu compositing is being used or is disabled for software // compositing. Clients of the compositor should give resources that match // the appropriate mode. bool IsGpuCompositingDisabled() { return is_gpu_compositing_disabled_; } // Synchronously establish a channel to the GPU plugin if not previously // established or if it has been lost (for example if the GPU plugin crashed). // If there is a pending asynchronous request, it will be completed by the // time this routine returns. scoped_refptr EstablishGpuChannelSync(); gpu::GpuMemoryBufferManager* GetGpuMemoryBufferManager(); using LayerTreeFrameSinkCallback = base::OnceCallback)>; void RequestNewLayerTreeFrameSink( int routing_id, scoped_refptr frame_swap_message_queue, const GURL& url, LayerTreeFrameSinkCallback callback, mojom::RenderFrameMetadataObserverClientRequest render_frame_metadata_observer_client_request, mojom::RenderFrameMetadataObserverPtr render_frame_metadata_observer_ptr, const char* client_name); blink::AssociatedInterfaceRegistry* GetAssociatedInterfaceRegistry(); std::unique_ptr RequestCopyOfOutputForLayoutTest( int32_t routing_id, std::unique_ptr request); // True if we are running layout tests. This currently disables forwarding // various status messages to the console, skips network error pages, and // short circuits size update and focus events. bool layout_test_mode() const { return !!layout_test_deps_; } void set_layout_test_dependencies( std::unique_ptr deps) { layout_test_deps_ = std::move(deps); } // Returns whether we are running layout tests with display compositor for // pixel dump enabled. It is meant to disable feature that require display // compositor while it is not enabled by default. // This should only be called if currently running in layout tests. bool LayoutTestModeUsesDisplayCompositorPixelDump() const { DCHECK(layout_test_deps_); return layout_test_deps_->UseDisplayCompositorPixelDump(); } discardable_memory::ClientDiscardableSharedMemoryManager* GetDiscardableSharedMemoryManagerForTest() { return discardable_shared_memory_manager_.get(); } RendererBlinkPlatformImpl* blink_platform_impl() const { DCHECK(blink_platform_impl_); return blink_platform_impl_.get(); } // Returns the task runner on the compositor thread. // // Will be null if threaded compositing has not been enabled. scoped_refptr compositor_task_runner() const { return compositor_task_runner_; } AppCacheDispatcher* appcache_dispatcher() const { return appcache_dispatcher_.get(); } DomStorageDispatcher* dom_storage_dispatcher() const { return dom_storage_dispatcher_.get(); } MidiMessageFilter* midi_message_filter() { return midi_message_filter_.get(); } ResourceDispatcher* resource_dispatcher() const { return resource_dispatcher_.get(); } URLLoaderThrottleProvider* url_loader_throttle_provider() const { return url_loader_throttle_provider_.get(); } #if defined(OS_ANDROID) scoped_refptr GetStreamTexureFactory(); bool EnableStreamTextureCopy(); #endif // Creates the embedder implementation of WebMediaStreamCenter. // The resulting object is owned by WebKit and deleted by WebKit at tear-down. std::unique_ptr CreateMediaStreamCenter(); BrowserPluginManager* browser_plugin_manager() const { return browser_plugin_manager_.get(); } #if BUILDFLAG(ENABLE_WEBRTC) // Returns a factory used for creating RTC PeerConnection objects. PeerConnectionDependencyFactory* GetPeerConnectionDependencyFactory(); PeerConnectionTracker* peer_connection_tracker() { return peer_connection_tracker_.get(); } // Current P2PSocketDispatcher. Set to NULL if P2P API is disabled. P2PSocketDispatcher* p2p_socket_dispatcher() { return p2p_socket_dispatcher_.get(); } #endif VideoCaptureImplManager* video_capture_impl_manager() const { return vc_manager_.get(); } LowMemoryModeController* low_memory_mode_controller() const { return low_memory_mode_controller_.get(); } mojom::RenderFrameMessageFilter* render_frame_message_filter(); mojom::RenderMessageFilter* render_message_filter(); // Get the GPU channel. Returns NULL if the channel is not established or // has been lost. gpu::GpuChannelHost* GetGpuChannel(); // Returns a SingleThreadTaskRunner instance corresponding to the message loop // of the thread on which media operations should be run. Must be called // on the renderer's main thread. scoped_refptr GetMediaThreadTaskRunner(); // A TaskRunner instance that runs tasks on the raster worker pool. base::TaskRunner* GetWorkerTaskRunner(); // Creates a ContextProvider if yet created, and returns it to be used for // video frame compositing. The ContextProvider given as an argument is // one that has been lost, and is a hint to the RenderThreadImpl to clear // it's |video_frame_compositor_context_provider_| if it matches. scoped_refptr GetVideoFrameCompositorContextProvider( scoped_refptr); // Returns a worker context provider that will be bound on the compositor // thread. scoped_refptr SharedCompositorWorkerContextProvider(); media::GpuVideoAcceleratorFactories* GetGpuFactories(); scoped_refptr SharedMainThreadContextProvider(); // AudioRendererMixerManager instance which manages renderer side mixer // instances shared based on configured audio parameters. Lazily created on // first call. AudioRendererMixerManager* GetAudioRendererMixerManager(); #if defined(OS_WIN) void PreCacheFontCharacters(const LOGFONT& log_font, const base::string16& str); #endif // For producing custom V8 histograms. Custom histograms are produced if all // RenderViews share the same host, and the host is in the pre-specified set // of hosts we want to produce custom diagrams for. The name for a custom // diagram is the name of the corresponding generic diagram plus a // host-specific suffix. class CONTENT_EXPORT HistogramCustomizer { public: HistogramCustomizer(); ~HistogramCustomizer(); // Called when a top frame of a RenderView navigates. This function updates // RenderThreadImpl's information about whether all RenderViews are // displaying a page from the same host. |host| is the host where a // RenderView navigated, and |view_count| is the number of RenderViews in // this process. void RenderViewNavigatedToHost(const std::string& host, size_t view_count); // Used for customizing some histograms if all RenderViews share the same // host. Returns the current custom histogram name to use for // |histogram_name|, or |histogram_name| if it shouldn't be customized. std::string ConvertToCustomHistogramName(const char* histogram_name) const; private: FRIEND_TEST_ALL_PREFIXES(RenderThreadImplUnittest, IdentifyAlexaTop10NonGoogleSite); friend class RenderThreadImplUnittest; // Converts a host name to a suffix for histograms std::string HostToCustomHistogramSuffix(const std::string& host); // Helper function to identify a certain set of top pages bool IsAlexaTop10NonGoogleSite(const std::string& host); // Used for updating the information on which is the common host which all // RenderView's share (if any). If there is no common host, this function is // called with an empty string. void SetCommonHost(const std::string& host); // The current common host of the RenderViews; empty string if there is no // common host. std::string common_host_; // The corresponding suffix. std::string common_host_histogram_suffix_; // Set of histograms for which we want to produce a custom histogram if // possible. std::set custom_histograms_; DISALLOW_COPY_AND_ASSIGN(HistogramCustomizer); }; HistogramCustomizer* histogram_customizer() { return &histogram_customizer_; } // Called by a RenderWidget when it is created or destroyed. This // allows the process to know when there are no visible widgets. void WidgetCreated(); // Note: A widget must not be hidden when it is destroyed - ensure that // WidgetRestored is called before WidgetDestroyed for any hidden widget. void WidgetDestroyed(); void WidgetHidden(); void WidgetRestored(); void RegisterPendingFrameCreate( const service_manager::BindSourceInfo& source_info, int routing_id, mojom::FrameRequest frame); blink::mojom::StoragePartitionService* GetStoragePartitionService(); mojom::RendererHost* GetRendererHost(); struct RendererMemoryMetrics { size_t partition_alloc_kb; size_t blink_gc_kb; size_t malloc_mb; size_t discardable_kb; size_t v8_main_thread_isolate_mb; size_t total_allocated_mb; size_t non_discardable_total_allocated_mb; size_t total_allocated_per_render_view_mb; }; bool GetRendererMemoryMetrics(RendererMemoryMetrics* memory_metrics) const; bool NeedsToRecordFirstActivePaint(int metric_type) const; // Sets the current pipeline rendering color space. void SetRenderingColorSpace(const gfx::ColorSpace& color_space); scoped_refptr CreateVideoFrameCompositorTaskRunner(); private: void OnProcessFinalRelease() override; // IPC::Listener void OnChannelError() override; // ChildThread bool OnControlMessageReceived(const IPC::Message& msg) override; void RecordAction(const base::UserMetricsAction& action) override; void RecordComputedAction(const std::string& action) override; bool IsMainThread(); void RecordPurgeMemory(RendererMemoryMetrics before); void Init(); void InitializeCompositorThread(); void InitializeWebKit(service_manager::BinderRegistry* registry); void OnTransferBitmap(const SkBitmap& bitmap, int resource_id); void OnGetAccessibilityTree(); // mojom::Renderer: void CreateEmbedderRendererService( service_manager::mojom::ServiceRequest service_request) override; void CreateView(mojom::CreateViewParamsPtr params) override; void CreateFrame(mojom::CreateFrameParamsPtr params) override; void CreateFrameProxy( int32_t routing_id, int32_t render_view_routing_id, int32_t opener_routing_id, int32_t parent_routing_id, const FrameReplicationState& replicated_state, const base::UnguessableToken& devtools_frame_token) override; void SetUpEmbeddedWorkerChannelForServiceWorker( mojom::EmbeddedWorkerInstanceClientRequest client_request) override; void OnNetworkConnectionChanged( net::NetworkChangeNotifier::ConnectionType type, double max_bandwidth_mbps) override; void OnNetworkQualityChanged(net::EffectiveConnectionType type, base::TimeDelta http_rtt, base::TimeDelta transport_rtt, double bandwidth_kbps) override; void SetWebKitSharedTimersSuspended(bool suspend) override; void SetUserAgent(const std::string& user_agent) override; void UpdateScrollbarTheme( mojom::UpdateScrollbarThemeParamsPtr params) override; void OnSystemColorsChanged(int32_t aqua_color_variant, const std::string& highlight_text_color, const std::string& highlight_color) override; void PurgePluginListCache(bool reload_pages) override; void SetProcessBackgrounded(bool backgrounded) override; void SetSchedulerKeepActive(bool keep_active) override; void ProcessPurgeAndSuspend() override; void SetIsLockedToSite() override; void EnableV8LowMemoryMode() override; void OnMemoryPressure( base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level); bool RendererIsHidden() const; void OnRendererHidden(); void OnRendererVisible(); void RecordMemoryUsageAfterBackgrounded(const char* suffix, int foregrounded_count); void RecordPurgeAndSuspendMemoryGrowthMetrics( const char* suffix, int foregrounded_count_when_purged); void ReleaseFreeMemory(); void OnSyncMemoryPressure( base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level); std::unique_ptr CreateSyntheticBeginFrameSource(); void OnRendererInterfaceRequest(mojom::RendererAssociatedRequest request); std::unique_ptr discardable_shared_memory_manager_; // These objects live solely on the render thread. std::unique_ptr appcache_dispatcher_; std::unique_ptr dom_storage_dispatcher_; std::unique_ptr main_thread_indexed_db_dispatcher_; std::unique_ptr main_thread_scheduler_; std::unique_ptr blink_platform_impl_; std::unique_ptr resource_dispatcher_; std::unique_ptr url_loader_throttle_provider_; // Used on the renderer and IPC threads. scoped_refptr midi_message_filter_; std::unique_ptr browser_plugin_manager_; #if BUILDFLAG(ENABLE_WEBRTC) std::unique_ptr peer_connection_factory_; // This is used to communicate to the browser process the status // of all the peer connections created in the renderer. std::unique_ptr peer_connection_tracker_; // Dispatches all P2P sockets. scoped_refptr p2p_socket_dispatcher_; // Used for communicating registering AEC dump consumers with the browser and // receving AEC dump file handles when AEC dump is enabled. An AEC dump is // diagnostic audio data for WebRTC stored locally when enabled by the user in // chrome://webrtc-internals. scoped_refptr aec_dump_message_filter_; #endif // Provides AudioInputIPC objects for audio input devices. Initialized in // Init. base::Optional audio_input_ipc_factory_; // Provides AudioOutputIPC objects for audio output devices. Initialized in // Init. base::Optional audio_output_ipc_factory_; // Used on the render thread. std::unique_ptr vc_manager_; // The count of RenderWidgets running through this thread. int widget_count_; // The count of hidden RenderWidgets running through this thread. int hidden_widget_count_; blink::WebString user_agent_; // Used to control layout test specific behavior. std::unique_ptr layout_test_deps_; // Sticky once true, indicates that compositing is done without Gpu, so // resources given to the compositor or to the viz service should be // software-based. bool is_gpu_compositing_disabled_ = false; // Utility class to provide GPU functionalities to media. // TODO(dcastagna): This should be just one scoped_ptr once // http://crbug.com/580386 is fixed. // NOTE(dcastagna): At worst this accumulates a few bytes per context lost. std::vector> gpu_factories_; // Thread for running multimedia operations (e.g., video decoding). std::unique_ptr media_thread_; // Will point to appropriate task runner after initialization, // regardless of whether |compositor_thread_| is overriden. scoped_refptr compositor_task_runner_; // Task to run the VideoFrameCompositor on. scoped_refptr video_frame_compositor_task_runner_; // Pool of workers used for raster operations (e.g., tile rasterization). scoped_refptr categorized_worker_pool_; #if defined(OS_ANDROID) scoped_refptr stream_texture_factory_; #endif scoped_refptr shared_main_thread_contexts_; base::ObserverList::Unchecked observers_; scoped_refptr video_frame_compositor_context_provider_; scoped_refptr shared_worker_context_provider_; std::unique_ptr audio_renderer_mixer_manager_; HistogramCustomizer histogram_customizer_; std::unique_ptr memory_pressure_listener_; // Created in response to EnableV8LowMemoryMode(), this manages V8's // memory saving mode. std::unique_ptr low_memory_mode_controller_; std::unique_ptr gpu_; scoped_refptr main_thread_compositor_task_runner_; // Compositor settings. bool is_gpu_rasterization_forced_; int gpu_rasterization_msaa_sample_count_; bool is_lcd_text_enabled_; bool is_zero_copy_enabled_; bool is_gpu_memory_buffer_compositor_resources_enabled_; bool is_partial_raster_enabled_; bool is_elastic_overscroll_enabled_; bool is_zoom_for_dsf_enabled_; bool is_threaded_animation_enabled_; bool is_scroll_animator_enabled_; // Target rendering ColorSpace. gfx::ColorSpace rendering_color_space_; class PendingFrameCreate : public base::RefCounted { public: PendingFrameCreate(const service_manager::BindSourceInfo& source_info, int routing_id, mojom::FrameRequest frame_request); const service_manager::BindSourceInfo& browser_info() const { return browser_info_; } mojom::FrameRequest TakeFrameRequest() { return std::move(frame_request_); } private: friend class base::RefCounted; ~PendingFrameCreate(); // Mojo error handler. void OnConnectionError(); service_manager::BindSourceInfo browser_info_; int routing_id_; mojom::FrameRequest frame_request_; }; using PendingFrameCreateMap = std::map>; PendingFrameCreateMap pending_frame_creates_; blink::mojom::StoragePartitionServicePtr storage_partition_service_; mojom::RendererHostAssociatedPtr renderer_host_; blink::AssociatedInterfaceRegistry associated_interfaces_; mojo::AssociatedBinding renderer_binding_; mojom::RenderFrameMessageFilterAssociatedPtr render_frame_message_filter_; mojom::RenderMessageFilterAssociatedPtr render_message_filter_; RendererMemoryMetrics purge_and_suspend_memory_metrics_; bool needs_to_record_first_active_paint_; base::TimeTicks was_backgrounded_time_; int process_foregrounded_count_; bool online_status_ = true; int32_t client_id_; mojom::FrameSinkProviderPtr frame_sink_provider_; // A mojo connection to the CompositingModeReporter service. viz::mojom::CompositingModeReporterPtr compositing_mode_reporter_; // The class is a CompositingModeWatcher, which is bound to mojo through // this member. mojo::Binding compositing_mode_watcher_binding_; base::WeakPtrFactory weak_factory_; DISALLOW_COPY_AND_ASSIGN(RenderThreadImpl); }; #if defined(COMPILER_MSVC) #pragma warning(pop) #endif } // namespace content #endif // CONTENT_RENDERER_RENDER_THREAD_IMPL_H_