Support cntrl-tab to switch tabs on OS X.
Support cntrl-tab to switch tabs on OS X.

BUG=13299
TEST=Cntrl-Tab should switch to the next tab, cntrl-shift-tab should switch to the previous tab.

Review URL: http://codereview.chromium.org/164133

git-svn-id: http://src.chromium.org/svn/trunk/src@22731 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 3467bbb5de4570ad97f308176605345f6c4e9a73
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