Allow immediate tasks to run even when virtual time can't advance

components/scheduler/renderer/web_view_scheduler_impl_unittest.cc

 // Copyright 2015 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/web_view_scheduler_impl.h"
 
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/test/simple_test_tick_clock.h"
 #include "cc/test/ordered_simple_task_runner.h"
@@ skipping 297 matching lines @@
         BLINK_FROM_HERE, new RunOrderTask(index_ + 1, out_run_order_));
   }
 
  private:
   int index_;
   blink::WebTaskRunner* task_runner_;  // NOT OWNED
   std::vector<int>* out_run_order_;    // NOT OWNED
 };
 }
 
-TEST_F(WebViewSchedulerImplTest, VirtualTime_DelayedAndImmediateTaskOrdering) {
+TEST_F(WebViewSchedulerImplTest, VirtualTime_NotAllowedToAdvance) {
   std::vector<int> run_order;
 
   web_view_scheduler_->setAllowVirtualTimeToAdvance(false);
   web_view_scheduler_->enableVirtualTime();
 
   web_frame_scheduler_->timerTaskRunner()->postTask(
       BLINK_FROM_HERE, new RunOrderTask(0, &run_order));
 
   web_frame_scheduler_->timerTaskRunner()->postDelayedTask(
       BLINK_FROM_HERE,
       new DelayedRunOrderTask(1, web_frame_scheduler_->timerTaskRunner(),
                               &run_order),
       2.0);
 
   web_frame_scheduler_->timerTaskRunner()->postDelayedTask(
       BLINK_FROM_HERE,
       new DelayedRunOrderTask(3, web_frame_scheduler_->timerTaskRunner(),
                               &run_order),
       4.0);
 
   mock_task_runner_->RunUntilIdle();
-  EXPECT_TRUE(run_order.empty());
+
+  // Immediate tasks are allowed to run even if delayed tasks are not.
+  EXPECT_THAT(run_order, ElementsAre(0));
+}
+
+TEST_F(WebViewSchedulerImplTest, VirtualTime_AllowedToAdvance) {
+  std::vector<int> run_order;
 
   web_view_scheduler_->setAllowVirtualTimeToAdvance(true);
+  web_view_scheduler_->enableVirtualTime();
+
+  web_frame_scheduler_->timerTaskRunner()->postTask(
+      BLINK_FROM_HERE, new RunOrderTask(0, &run_order));
+
+  web_frame_scheduler_->timerTaskRunner()->postDelayedTask(
+      BLINK_FROM_HERE,
+      new DelayedRunOrderTask(1, web_frame_scheduler_->timerTaskRunner(),
+                              &run_order),
+      2.0);
+
+  web_frame_scheduler_->timerTaskRunner()->postDelayedTask(
+      BLINK_FROM_HERE,
+      new DelayedRunOrderTask(3, web_frame_scheduler_->timerTaskRunner(),
+                              &run_order),
+      4.0);
+
   mock_task_runner_->RunUntilIdle();
 
   EXPECT_THAT(run_order, ElementsAre(0, 1, 2, 3, 4));
 }
 
 class WebViewSchedulerImplTestWithDisabledBackgroundTimerThrottling
     : public WebViewSchedulerImplTest {
  public:
   WebViewSchedulerImplTestWithDisabledBackgroundTimerThrottling() {}
   ~WebViewSchedulerImplTestWithDisabledBackgroundTimerThrottling() override {}
@@ skipping 17 matching lines @@
 
 TEST_F(WebViewSchedulerImplTest, VirtualTimeSettings_NewWebFrameScheduler) {
   std::vector<int> run_order;
 
   web_view_scheduler_->setAllowVirtualTimeToAdvance(false);
   web_view_scheduler_->enableVirtualTime();
 
   scoped_ptr<WebFrameSchedulerImpl> web_frame_scheduler =
       web_view_scheduler_->createWebFrameSchedulerImpl();
 
-  web_frame_scheduler->timerTaskRunner()->postTask(
-      BLINK_FROM_HERE, new RunOrderTask(1, &run_order));
+  web_frame_scheduler->timerTaskRunner()->postDelayedTask(
+      BLINK_FROM_HERE, new RunOrderTask(1, &run_order), 0.1);
 
   mock_task_runner_->RunUntilIdle();
   EXPECT_TRUE(run_order.empty());
 
   web_view_scheduler_->setAllowVirtualTimeToAdvance(true);
   mock_task_runner_->RunUntilIdle();
 
   EXPECT_THAT(run_order, ElementsAre(1));
 }
 
@@ skipping 63 matching lines @@
   // it will prevent further tasks from running (i.e. the RepeatingTask) by
   // deleting the WebFrameScheduler.
   timer_task_runner->postDelayedTask(BLINK_FROM_HERE, delete_frame_task,
                                      9990.0);
 
   mock_task_runner_->RunForPeriod(base::TimeDelta::FromSeconds(100));
   EXPECT_EQ(10, run_count);
 }
 
 }  // namespace scheduler