DOMUI Prefs: Improve focus appearance on Mac
DOMUI Prefs: Improve focus appearance on Mac

Partially styling focus rings on the Mac looks weird, and we can't do completely custom styling that looks good until outlines follow border-radius correctly, so use the standard OS look. Also adjust button focus ring location on the Mac to adjust for changes to button elements.

BUG=None
TEST=Focus rings in DOMUI prefs should look have the standard platform look on the Mac.

Review URL: http://codereview.chromium.org/6320015

git-svn-id: http://src.chromium.org/svn/trunk/src@72572 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 579171c4a23f4b7efe9bd808e009a43408d87e01
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser