GitLab

1) Initial shift key sanity checks
2) Highlighting capitalization
3) Chording base cases.
4) Capitalization on long press.
5) Capitalization on double click.
BUG=295049

Review URL: https://codereview.chromium.org/25305003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@226513 0039d316-1c4b-4281-b951-d872f2087c98