Running delayed tasks immediately in ServiceWorkerRegistrationTest

This patch uses TimeSource::MOCK_TIME trait to construct ScopedTaskEnvironment,
which will enable the delayed tasks to be handled when reaching idle.

By doing so, we can get rid of the usage of RunUntilActivated().

Bug: 988930
Change-Id: I6c3ea276e7ce300eb525c886404c1e54a312a0c3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1747858Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Commit-Queue: Minggang Wang <minggang.wang@intel.com>
Cr-Commit-Position: refs/heads/master@{#686739}

content/browser/service_worker/service_worker_registration_unittest.cc

@@ -173,7 +173,8 @@ class MockServiceWorkerRegistrationObject
 class ServiceWorkerRegistrationTest : public testing::Test {
  public:
   ServiceWorkerRegistrationTest()
-      : thread_bundle_(TestBrowserThreadBundle::IO_MAINLOOP) {}
+      : thread_bundle_(base::test::ScopedTaskEnvironment::TimeSource::MOCK_TIME,
+                       TestBrowserThreadBundle::IO_MAINLOOP) {}
 
   void SetUp() override {
     helper_ = std::make_unique<EmbeddedWorkerTestHelper>(base::FilePath());
@@ -570,8 +571,6 @@ TEST_P(ServiceWorkerActivationTest, NoInflightRequest) {
   scoped_refptr<ServiceWorkerRegistration> reg = registration();
   scoped_refptr<ServiceWorkerVersion> version_1 = reg->active_version();
   scoped_refptr<ServiceWorkerVersion> version_2 = reg->waiting_version();
-  auto runner = base::MakeRefCounted<base::TestSimpleTaskRunner>();
-  reg->SetTaskRunnerForTest(runner);
 
   // Remove the controllee. Since there is an in-flight request,
   // activation should not yet happen.
@@ -588,7 +587,9 @@ TEST_P(ServiceWorkerActivationTest, NoInflightRequest) {
   RequestTermination(&version_1_client()->host());
 
   TestServiceWorkerObserver observer(helper_->context_wrapper());
-  observer.RunUntilActivated(version_2.get(), runner);
+  observer.RunUntilStatusChange(version_2.get(),
+                                ServiceWorkerVersion::ACTIVATED);
+  EXPECT_EQ(ServiceWorkerVersion::ACTIVATED, version_2->status());
   EXPECT_EQ(version_2.get(), reg->active_version());
 }