Attempt at making ToplevelWindowEventHandlerTest.RunMoveLoopFailsDuringInProgressDrag less flaky

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

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=251899

[pkotwicz, 2014-02-16 02:18:15]

James, can you please take a look?

I suspect that all of ToplevelWindowEventHandlerTest are flaky from time to
time. However, the flakiness dashboard does not have any entries for any of
ToplevelWindowEventHandlerTest for Win8 Aura
http://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=...

[James Cook, 2014-02-18 19:13:59]

LGTM

[pkotwicz, 2014-02-18 19:55:07]

The CQ bit was checked by pkotwicz@chromium.org

[commit-bot: I haz the power, 2014-02-18 19:56:12]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/pkotwicz@chromium.org/168793002/1

[commit-bot: I haz the power, 2014-02-18 21:05:11]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-02-18 21:05:12]

Retried try job too often on win_rel for step(s) unit_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[pkotwicz, 2014-02-18 22:15:53]

The CQ bit was checked by pkotwicz@chromium.org

[commit-bot: I haz the power, 2014-02-18 22:16:51]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/pkotwicz@chromium.org/168793002/1

[commit-bot: I haz the power, 2014-02-19 00:33:07]

Change committed as 251899