Don't animate child windows if animations are disabled in Windows.

BUG=338413
R=sky@chromium.org, sky

Review URL: https://codereview.chromium.org/130893009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248630 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 248630