GitLab

This plumbs through keys like backspace and enter and arrow keys.
It also provides Unicode characters for displays with query keyboards etc.

BUG=310285
R=dtseng@chromium.org, kalman@chromium.org

Review URL: https://codereview.chromium.org/297833015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@273171 0039d316-1c4b-4281-b951-d872f2087c98