Filter modifier to only include accelerator modifiers.
Filter modifier to only include accelerator modifiers.

Review URL: http://codereview.chromium.org/99103

git-svn-id: http://src.chromium.org/svn/trunk/src@14690 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 5a248c08010f5a1fefc89efee4390683f477c570
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