Revert 263507 "Moves transient parent together with its children..."
New test fails on win8 builder: http://build.chromium.org/p/chromium.win/builders/Win8%20Aura/builds/18140/steps/ash_unittests/logs/AutoPlacingMovesTransientChild
> Moves transient parent together with its children when auto-positioning
>
> BUG=362197
> TEST=ash_unittests --gtest_filter=WorkspaceControllerTest.AutoPlacingMovesTransientChild
> TEST=Repeat the repro steps in the bug
>
> Review URL: https://codereview.chromium.org/
233853002
TBR=varkha@chromium.org
Review URL: https://codereview.chromium.org/
235883003
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@263532 0039d316-1c4b-4281-b951-d872f2087c98