Adds a flag to support "Virtual Time" to the blink scheduler

components/scheduler/child/virtual_time_task_runner_delegate_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/child/virtual_time_task_runner_delegate.h"
+
+#include "base/bind.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace scheduler {
+
+class VirtualTimeTaskRunnerDelegateTest : public testing::Test {
+ public:
+  VirtualTimeTaskRunnerDelegateTest() {}
+
+  ~VirtualTimeTaskRunnerDelegateTest() override {}
+
+  void SetUp() override {
+    message_loop_.reset(new base::MessageLoop());
+    initial_time_ = base::TimeTicks() + base::TimeDelta::FromSeconds(100);
+    virtual_time_task_runner_delegate_ =
+        VirtualTimeTaskRunnerDelegate::Create(message_loop_.get(),
+                                              initial_time_);
+  }
+
+  base::TimeTicks initial_time_;
+  scoped_ptr<base::MessageLoop> message_loop_;
+
+  scoped_refptr<VirtualTimeTaskRunnerDelegate>
+      virtual_time_task_runner_delegate_;
+};
+
+namespace {
+void TestFunc(bool* run) {
+  *run = true;
+}
+}
+
+TEST_F(VirtualTimeTaskRunnerDelegateTest, OnNoMoreWork_FastForwardingEnabled) {
+  bool was_run = false;
+  virtual_time_task_runner_delegate_->PostDelayedTask(
+      FROM_HERE,
+      base::Bind(TestFunc, &was_run),
+      base::TimeDelta::FromSeconds(1));
+
+  EXPECT_EQ(initial_time_, virtual_time_task_runner_delegate_->NowTicks());
+
+  virtual_time_task_runner_delegate_->OnNoMoreWork();
+
+  EXPECT_EQ(initial_time_ + base::TimeDelta::FromSeconds(1),
+            virtual_time_task_runner_delegate_->NowTicks());
+
+  message_loop_->RunUntilIdle();
+  EXPECT_TRUE(was_run);
+}
+
+TEST_F(VirtualTimeTaskRunnerDelegateTest, OnNoMoreWork_FastForwardingDisabled) {
+  bool was_run = false;
+  virtual_time_task_runner_delegate_->PostDelayedTask(
+      FROM_HERE,
+      base::Bind(TestFunc, &was_run),
+      base::TimeDelta::FromSeconds(1));
+
+  virtual_time_task_runner_delegate_->SetFastForwardTimers(false);
+
+  EXPECT_EQ(initial_time_, virtual_time_task_runner_delegate_->NowTicks());
+
+  virtual_time_task_runner_delegate_->OnNoMoreWork();
+
+  EXPECT_EQ(initial_time_, virtual_time_task_runner_delegate_->NowTicks());
+
+  message_loop_->RunUntilIdle();
+  EXPECT_FALSE(was_run);
+}
+
+}  // namespace scheduler