Expose different task runner in RenderFrame for convenience

content/renderer/render_frame_impl.h

Index: content/renderer/render_frame_impl.h
diff --git a/content/renderer/render_frame_impl.h b/content/renderer/render_frame_impl.h
index f4159894cc4a79d17c5a222ead66b614c8297cf2..dc2d7bad51478321a910145b8a4d92b4a87db351 100644
--- a/content/renderer/render_frame_impl.h
+++ b/content/renderer/render_frame_impl.h
@@ -24,6 +24,7 @@
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
 #include "base/process/process_handle.h"
+#include "base/single_thread_task_runner.h"
 #include "build/build_config.h"
 #include "content/common/accessibility_mode_enums.h"
 #include "content/common/associated_interface_registry_impl.h"
@@ -454,6 +455,9 @@ class CONTENT_EXPORT RenderFrameImpl
   bool IsPasting() const override;
   blink::WebPageVisibilityState GetVisibilityState() const override;
   bool IsBrowserSideNavigationPending() override;
+  base::SingleThreadTaskRunner* GetTimerTaskRunner() override;
+  base::SingleThreadTaskRunner* GetLoadingTaskRunner() override;
+  base::SingleThreadTaskRunner* GetUnthrottledTaskRunner() override;
 
   // blink::mojom::EngagementClient implementation:
   void SetEngagementLevel(const url::Origin& origin,