Implement undo/redo so they will be properly enabled when the web content has focus. BUG=26112 TEST=per bug. Review URL: http://codereview.chromium.org/355016
Implement undo/redo so they will be properly enabled when the web content has focus.
BUG=26112
TEST=per bug.
Review URL: http://codereview.chromium.org/355016

git-svn-id: http://src.chromium.org/svn/trunk/src@30958 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 856471260f4f6f37a2e4f7d65af2d0a81e86204c
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