cc: Remove the --enable-partial-swap flag.

R=piman
BUG=

Review URL: https://codereview.chromium.org/167953003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251898 0039d316-1c4b-4281-b951-d872f2087c98
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
SVN changes up to revision 251899