Attempt at making ToplevelWindowEventHandlerTest.RunMoveLoopFailsDuringInProgressDrag less flaky

The test seems to pass fine when I run it manually on Windows Ash (including with high values of --gtest_repeat)
This CL:
- Makes ToplevelWindowEventHandlerTest.RunMoveLoopFailsDuringInProgressDrag look more like ToplevelWindowEventHandlerTest.Caption which I don't think is flaky on Windows Ash.
- Adds an extra check which will help better understand the source of the flakiness should it occur again

BUG=343167
TEST=None

Review URL: https://codereview.chromium.org/168793002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251899 0039d316-1c4b-4281-b951-d872f2087c98

ash/wm/toplevel_window_event_handler_unittest.cc

@@ -724,7 +724,7 @@ TEST_F(ToplevelWindowEventHandlerTest, RunMoveLoopFailsDuringInProgressDrag) {
   window1->Focus();
   generator.PressLeftButton();
   generator.MoveMouseBy(10, 11);
-  RunAllPendingInMessageLoop();
+  EXPECT_EQ("10,11 100x100", window1->bounds().ToString());
 
   aura::client::WindowMoveClient* move_client =
       aura::client::GetWindowMoveClient(window2->GetRootWindow());
@@ -733,7 +733,6 @@ TEST_F(ToplevelWindowEventHandlerTest, RunMoveLoopFailsDuringInProgressDrag) {
                 aura::client::WINDOW_MOVE_SOURCE_MOUSE));
 
   generator.ReleaseLeftButton();
-  RunAllPendingInMessageLoop();
   EXPECT_EQ("10,11 100x100", window1->bounds().ToString());
 }