aw: Fix hardware rendering from r254295

Need to set GlobalVisibleRect before testing it's empty.

BUG=344087
NOTRY=true

Review URL: https://codereview.chromium.org/184103020

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254531 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 254531