Make nesting/running states a RunLoop rather than a MessageLoop concept.

ui/aura/window_event_dispatcher_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 "ui/aura/window_event_dispatcher.h"
 
 #include <stddef.h>
 
 #include <utility>
 #include <vector>
@@ skipping 2066 matching lines @@
     dispatcher->RepostEvent(event.get());
   }
 
   std::unique_ptr<Window> window_;
   ExitMessageLoopOnMousePress handler_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowEventDispatcherTestWithMessageLoop);
 };
 
 TEST_P(WindowEventDispatcherTestWithMessageLoop, EventRepostedInNonNestedLoop) {
-  CHECK(!message_loop()->is_running());
+  ASSERT_FALSE(base::RunLoop::IsRunningOnCurrentThread());
   // Perform the test in a callback, so that it runs after the message-loop
   // starts.
   message_loop()->task_runner()->PostTask(
       FROM_HERE, base::Bind(&WindowEventDispatcherTestWithMessageLoop::RunTest,
                             base::Unretained(this)));
   base::RunLoop().Run();
 }
 
 class WindowEventDispatcherTestInHighDPI : public WindowEventDispatcherTest {
  public:
@@ skipping 817 matching lines @@
   EXPECT_EQ(1, last_event_location_delegate.mouse_event_count());
   EXPECT_EQ(1, last_event_location_delegate.nested_message_loop_count());
   EXPECT_EQ(mouse_location, last_event_location_delegate.last_mouse_location());
 
   // After dispatch the location should fallback to that of the
   // WindowTreeClient, which defaults to 0,0.
   EXPECT_EQ(gfx::Point(0, 0), Env::GetInstance()->last_mouse_location());
 }
 
 }  // namespace aura