Revert of Move throttling of background timers into the renderer scheduler

components/scheduler/renderer/webthread_impl_for_renderer_scheduler_unittest.cc

Index: components/scheduler/renderer/webthread_impl_for_renderer_scheduler_unittest.cc
diff --git a/components/scheduler/renderer/webthread_impl_for_renderer_scheduler_unittest.cc b/components/scheduler/renderer/webthread_impl_for_renderer_scheduler_unittest.cc
index c19e75e54f51fee329e1aaa7ba2c2c2efb81d329..52f4ee85f928ee9bfb9b515b717f2304ae76e805 100644
--- a/components/scheduler/renderer/webthread_impl_for_renderer_scheduler_unittest.cc
+++ b/components/scheduler/renderer/webthread_impl_for_renderer_scheduler_unittest.cc
@@ -35,30 +35,27 @@
 
 class WebThreadImplForRendererSchedulerTest : public testing::Test {
  public:
-  WebThreadImplForRendererSchedulerTest() {}
-
-  void SetUp() override {
-    clock_.reset(new base::SimpleTestTickClock());
-    clock_->Advance(base::TimeDelta::FromMicroseconds(5000));
-    scheduler_.reset(new RendererSchedulerImpl(SchedulerTqmDelegateImpl::Create(
-        &message_loop_, make_scoped_ptr(new TestTimeSource(clock_.get())))));
-    default_task_runner_ = scheduler_->DefaultTaskRunner();
-    thread_ = scheduler_->CreateMainThread();
-  }
+  WebThreadImplForRendererSchedulerTest()
+      : clock_(new base::SimpleTestTickClock()),
+        scheduler_(SchedulerTqmDelegateImpl::Create(
+            &message_loop_,
+            make_scoped_ptr(new TestTimeSource(clock_.get())))),
+        default_task_runner_(scheduler_.DefaultTaskRunner()),
+        thread_(scheduler_.CreateMainThread()) {}
 
   ~WebThreadImplForRendererSchedulerTest() override {}
 
   void SetWorkBatchSizeForTesting(size_t work_batch_size) {
-    scheduler_->GetSchedulerHelperForTesting()->SetWorkBatchSizeForTesting(
+    scheduler_.GetSchedulerHelperForTesting()->SetWorkBatchSizeForTesting(
         work_batch_size);
   }
 
-  void TearDown() override { scheduler_->Shutdown(); }
+  void TearDown() override { scheduler_.Shutdown(); }
 
  protected:
   base::MessageLoop message_loop_;
   scoped_ptr<base::SimpleTestTickClock> clock_;
-  scoped_ptr<RendererSchedulerImpl> scheduler_;
+  RendererSchedulerImpl scheduler_;
   scoped_refptr<base::SingleThreadTaskRunner> default_task_runner_;
   scoped_ptr<blink::WebThread> thread_;