scheduler: Turn expensive task blocking into a finch trial

components/scheduler/renderer/renderer_scheduler_impl_unittest.cc

 // Copyright 2014 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 "components/scheduler/renderer/renderer_scheduler_impl.h"
 
 #include <utility>
 
 #include "base/callback.h"
 #include "base/macros.h"
@@ skipping 2213 matching lines @@
 
   EXPECT_EQ(UseCase::MAIN_THREAD_GESTURE,
             ForceUpdatePolicyAndGetCurrentUseCase());
   EXPECT_TRUE(HaveSeenABeginMainframe());
   EXPECT_FALSE(LoadingTasksSeemExpensive());
   EXPECT_TRUE(TimerTasksSeemExpensive());
   EXPECT_TRUE(TouchStartExpectedSoon());
   EXPECT_THAT(run_order, testing::ElementsAre(std::string("D1")));
 }
 
+TEST_F(RendererSchedulerImplTest, ExpensiveTimerTaskNotBlockedIfDisallowed) {
+  std::vector<std::string> run_order;
+
+  EnableTaskBlocking();
+  scheduler_->SetExpensiveTaskBlockingAllowed(false);
+  scheduler_->SetHasVisibleRenderWidgetWithTouchHandler(true);
+  DoMainFrame();
+  SimulateExpensiveTasks(timer_task_runner_);
+  ForceTouchStartToBeExpectedSoon();
+
+  scheduler_->DidHandleInputEventOnCompositorThread(
+      FakeInputEvent(blink::WebInputEvent::GestureFlingStart),
+      RendererScheduler::InputEventState::EVENT_FORWARDED_TO_MAIN_THREAD);
+  PostTestTasks(&run_order, "T1 D1");
+  RunUntilIdle();
+
+  EXPECT_EQ(UseCase::MAIN_THREAD_GESTURE,
+            ForceUpdatePolicyAndGetCurrentUseCase());
+  EXPECT_TRUE(HaveSeenABeginMainframe());
+  EXPECT_FALSE(LoadingTasksSeemExpensive());
+  EXPECT_TRUE(TimerTasksSeemExpensive());
+  EXPECT_TRUE(TouchStartExpectedSoon());
+  EXPECT_THAT(run_order, testing::ElementsAre(std::string("T1"),
+                                              std::string("D1")));
+}
+
 TEST_F(RendererSchedulerImplTest,
        ExpensiveTimerTaskBlockedIfTouchStartNotSeen) {
   std::vector<std::string> run_order;
 
   scheduler_->SetHasVisibleRenderWidgetWithTouchHandler(true);
   DoMainFrame();
   SimulateExpensiveTasks(timer_task_runner_);
   ForceTouchStartToBeExpectedSoon();
 
   scheduler_->DidHandleInputEventOnCompositorThread(
@@ skipping 233 matching lines @@
     }
 
     base::TimeDelta time_till_next_frame =
         EstimatedNextFrameBegin() - clock_->NowTicks();
     if (time_till_next_frame > base::TimeDelta())
       clock_->Advance(time_till_next_frame);
   }
 }
 
 }  // namespace scheduler