Revert of Ensure BrowserThread::CurrentlyOn is correct through MessageLoop teardown

content/browser/browser_thread_unittest.cc

 // Copyright (c) 2012 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 <memory>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/location.h"
-#include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/sequenced_task_runner_helpers.h"
 #include "base/single_thread_task_runner.h"
-#include "base/threading/thread_task_runner_handle.h"
 #include "content/browser/browser_thread_impl.h"
 #include "content/public/test/test_browser_thread.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/platform_test.h"
 
 namespace content {
 
 class BrowserThreadTest : public testing::Test {
  public:
   void Release() const {
     CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
     loop_.task_runner()->PostTask(FROM_HERE,
                                   base::MessageLoop::QuitWhenIdleClosure());
   }
 
-  void StopFileThread() {
-    file_thread_->Stop();
-  }
-
  protected:
   void SetUp() override {
     ui_thread_.reset(new BrowserThreadImpl(BrowserThread::UI));
     file_thread_.reset(new BrowserThreadImpl(BrowserThread::FILE));
     ui_thread_->Start();
     file_thread_->Start();
   }
 
   void TearDown() override {
     ui_thread_->Stop();
-    StopFileThread();
+    file_thread_->Stop();
   }
 
   static void BasicFunction(base::MessageLoop* message_loop) {
     CHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
     message_loop->task_runner()->PostTask(
         FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
   }
 
   class DeletedOnFile
       : public base::RefCountedThreadSafe<
@@ skipping 16 matching lines @@
   };
 
  private:
   std::unique_ptr<BrowserThreadImpl> ui_thread_;
   std::unique_ptr<BrowserThreadImpl> file_thread_;
   // It's kind of ugly to make this mutable - solely so we can post the Quit
   // Task from Release(). This should be fixed.
   mutable base::MessageLoop loop_;
 };
 
-class FileThreadDestructionObserver
-    : public base::MessageLoop::DestructionObserver {
- public:
-  explicit FileThreadDestructionObserver(bool* did_shutdown,
-                                         const base::Closure& callback)
-      : callback_task_runner_(base::ThreadTaskRunnerHandle::Get()),
-        callback_(callback),
-        file_task_runner_(
-            BrowserThread::GetTaskRunnerForThread(BrowserThread::FILE)),
-        did_shutdown_(did_shutdown) {
-    BrowserThread::GetTaskRunnerForThread(BrowserThread::FILE)->PostTask(
-        FROM_HERE, base::Bind(&Watch, this));
-  }
-
- private:
-  static void Watch(FileThreadDestructionObserver* observer) {
-    base::MessageLoop::current()->AddDestructionObserver(observer);
-  }
-
-  // base::MessageLoop::DestructionObserver:
-  void WillDestroyCurrentMessageLoop() override {
-    // Ensure that even during MessageLoop teardown the BrowserThread ID is
-    // correctly associated with this thread and the BrowserThreadTaskRunner
-    // knows it's on the right thread.
-    EXPECT_TRUE(BrowserThread::CurrentlyOn(BrowserThread::FILE));
-    EXPECT_TRUE(file_task_runner_->BelongsToCurrentThread());
-
-    base::MessageLoop::current()->RemoveDestructionObserver(this);
-    *did_shutdown_ = true;
-    callback_task_runner_->PostTask(FROM_HERE, callback_);
-  }
-
-  const scoped_refptr<base::SingleThreadTaskRunner> callback_task_runner_;
-  const base::Closure callback_;
-  const scoped_refptr<base::SingleThreadTaskRunner> file_task_runner_;
-  bool* did_shutdown_;
-};
-
 TEST_F(BrowserThreadTest, PostTask) {
   BrowserThread::PostTask(
       BrowserThread::FILE,
       FROM_HERE,
       base::Bind(&BasicFunction, base::MessageLoop::current()));
   base::RunLoop().Run();
 }
 
 TEST_F(BrowserThreadTest, Release) {
   BrowserThread::ReleaseSoon(BrowserThread::UI, FROM_HERE, this);
@@ skipping 26 matching lines @@
 TEST_F(BrowserThreadTest, PostTaskAndReply) {
   // Most of the heavy testing for PostTaskAndReply() is done inside the
   // task runner test.  This just makes sure we get piped through at all.
   ASSERT_TRUE(BrowserThread::PostTaskAndReply(
       BrowserThread::FILE, FROM_HERE, base::Bind(&base::DoNothing),
       base::Bind(&base::MessageLoop::QuitWhenIdle,
                  base::Unretained(base::MessageLoop::current()->current()))));
   base::RunLoop().Run();
 }
 
-TEST_F(BrowserThreadTest, RunsTasksOnCurrentThreadDuringShutdown) {
-  bool did_shutdown = false;
-  base::RunLoop loop;
-  FileThreadDestructionObserver observer(&did_shutdown, loop.QuitClosure());
-  base::ThreadTaskRunnerHandle::Get()->PostTask(
-      FROM_HERE,
-      base::Bind(&BrowserThreadTest::StopFileThread, base::Unretained(this)));
-  loop.Run();
-
-  EXPECT_TRUE(did_shutdown);
-}
-
 }  // namespace content