Use ScopedTaskEnvironment instead of MessageLoop in tests that use v8.

gin/modules/timer_unittest.cc

 // Copyright 2013 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 "gin/modules/timer.h"
 
 #include <memory>
 
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
@@ skipping 49 matching lines @@
         scope(runner.get()),
         timer_module(TimerModule::Create(isolate)),
         result(Result::Create(isolate)) {
     EXPECT_FALSE(runner->global().IsEmpty());
     runner->global()->Set(StringToV8(isolate, "timer"),
                           timer_module->GetWrapper(isolate).ToLocalChecked());
     runner->global()->Set(StringToV8(isolate, "result"),
                           result->GetWrapper(isolate).ToLocalChecked());
   }
 
-  void QuitSoon(base::MessageLoop* message_loop) {
-    message_loop->task_runner()->PostDelayedTask(
-        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure(),
-        base::TimeDelta::FromMilliseconds(0));
-  }
-
   ShellRunnerDelegate delegate;
   std::unique_ptr<ShellRunner> runner;
   Runner::Scope scope;
   Handle<TimerModule> timer_module;
   Handle<Result> result;
 };
 
 }  // namespace
 
 typedef V8Test TimerUnittest;
 
 TEST_F(TimerUnittest, OneShot) {
   TestHelper helper(instance_->isolate());
   std::string source =
      "timer.createOneShot(0, function() {"
      "  result.count++;"
      "});";
 
   helper.runner->Run(source, "script");
   EXPECT_EQ(0, helper.result->count());
 
-  helper.QuitSoon(&message_loop_);
-  base::RunLoop().Run();
+  base::RunLoop().RunUntilIdle();
   EXPECT_EQ(1, helper.result->count());
 }
 
 TEST_F(TimerUnittest, OneShotCancel) {
   TestHelper helper(instance_->isolate());
   std::string source =
      "var t = timer.createOneShot(0, function() {"
      "  result.count++;"
      "});"
      "t.cancel()";
 
   helper.runner->Run(source, "script");
   EXPECT_EQ(0, helper.result->count());
 
-  helper.QuitSoon(&message_loop_);
-  base::RunLoop().Run();
+  base::RunLoop().RunUntilIdle();
   EXPECT_EQ(0, helper.result->count());
 }
 
 TEST_F(TimerUnittest, Repeating) {
   TestHelper helper(instance_->isolate());
 
   // TODO(aa): Cannot do: if (++result.count == 3) because of v8 bug. Create
   // test case and report.
   std::string source =
-     "timer.createRepeating(0, function() {"
-     "  result.count++;"
-     "  if (result.count == 3) {"
-     "    result.quit();"
-     "  }"
-     "});";
+      "var t = timer.createRepeating(0, function() {"
+      "  result.count++;"
+      "  if (result.count == 3) {"
+      "    /* Cancel the timer to prevent a hang when ScopedTaskEnvironment "
+      "       flushes main thread tasks. */"
+      "    t.cancel();"
+      "    result.quit();"
+      "  }"
+      "});";
 
   helper.runner->Run(source, "script");
   EXPECT_EQ(0, helper.result->count());
 
   base::RunLoop().Run();
   EXPECT_EQ(3, helper.result->count());
 }
 
 TEST_F(TimerUnittest, TimerCallbackToDestroyedRunner) {
   TestHelper helper(instance_->isolate());
   std::string source =
      "timer.createOneShot(0, function() {"
      "  result.count++;"
      "});";
 
   helper.runner->Run(source, "script");
   EXPECT_EQ(0, helper.result->count());
 
   // Destroy runner, which should destroy the timer object we created.
-  helper.QuitSoon(&message_loop_);
   helper.runner.reset(NULL);
-  base::RunLoop().Run();
+  base::RunLoop().RunUntilIdle();
 
   // Timer should not have run because it was deleted.
   EXPECT_EQ(0, helper.result->count());
 }
 
 }  // namespace gin