Pass a task runner to base::Timer at RenderViewImpl

This is part of efforts to replace base::ThreadTaskRunnerHandle::Get()
and SequencedTaskRunnerHandle::Get() with other appropriate task runners
in the renderer.

This avoids the SequencedTaskRunnerHandle::Get() call when the constructor's
default parameter is used. We are trying to ban SequencedTaskRunnerHandle::Get()
in content/renderer because it usually is not the right task runner to use,
as a per-frame runner should be used instead. In this case, it doesn't
really matter since frames are not involved, but we still want to remove the
calls for the bigger benefit of banning it in content/renderer.

Bug: 786332
Change-Id: I96a5c6657c029bd685e2302a778316b69b3af683
Reviewed-on: https://chromium-review.googlesource.com/942287
Commit-Queue: Hajime Hoshi <hajimehoshi@chromium.org>
Reviewed-by: Alexander Timin <altimin@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#540820}

content/renderer/render_view_impl.cc

@@ -505,7 +505,8 @@ RenderViewImpl::RenderViewImpl(
 
 void RenderViewImpl::Initialize(
     mojom::CreateViewParamsPtr params,
-    const RenderWidget::ShowCallback& show_callback) {
+    const RenderWidget::ShowCallback& show_callback,
+    scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
   bool was_created_by_renderer = !show_callback.is_null();
 #if defined(OS_ANDROID)
   // TODO(sgurun): crbug.com/325351 Needed only for android webview's deprecated
@@ -622,6 +623,9 @@ void RenderViewImpl::Initialize(
   GetContentClient()->renderer()->RenderViewCreated(this);
 
   page_zoom_level_ = params->page_zoom_level;
+
+  nav_state_sync_timer_.SetTaskRunner(task_runner);
+  check_preferred_size_timer_.SetTaskRunner(std::move(task_runner));
 }
 
 RenderViewImpl::~RenderViewImpl() {
@@ -994,7 +998,8 @@ RenderViewImpl* RenderViewImpl::Create(
   else
     render_view = new RenderViewImpl(compositor_deps, *params, task_runner);
 
-  render_view->Initialize(std::move(params), show_callback);
+  render_view->Initialize(std::move(params), show_callback,
+                          std::move(task_runner));
   return render_view;
 }
 

content/renderer/render_view_impl.h

@@ -392,7 +392,8 @@ class CONTENT_EXPORT RenderViewImpl : public RenderWidget,
                  scoped_refptr<base::SingleThreadTaskRunner> task_runner);
 
   void Initialize(mojom::CreateViewParamsPtr params,
-                  const RenderWidget::ShowCallback& show_callback);
+                  const RenderWidget::ShowCallback& show_callback,
+                  scoped_refptr<base::SingleThreadTaskRunner> task_runner);
   void SetScreenMetricsEmulationParameters(
       bool enabled,
       const blink::WebDeviceEmulationParams& params) override;