apps/extensions: add "..." to the end of "Remove from Chrome{e,ium}".
This affects context menus on chrome://apps and right clicking extension icons.
We generally match Windows menu items here, which basically go by the ideology
"if there is more to do after activating this command, add a ... to the end".
http://msdn.microsoft.com/en-us/library/windows/desktop/dn742392%28v=vs.85%29.aspx
I interpret the "Really remove?" prompt after clicking the item as "more to do".
R=sky@chromium.org
BUG=440366
Review URL: https://codereview.chromium.org/
789413002
Cr-Commit-Position: refs/heads/master@{#307937}