Revert "Disable the XP presentation path (GPU direct) for Chrome Frame."

This reverts r234376 since Chrome Frame is now gone.

BUG=316496,316934
R=ananta@chromium.org
TBR=kbr@chromium.org

Review URL: https://codereview.chromium.org/142933005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246691 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 246691
Only call GetIdleWakeupsPerSecond() on OS X.

BUG=120488,337066
R=mark@chromium.org

Review URL: https://codereview.chromium.org/144753003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246692 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 246692