Hide "Remove" menu & the drag handle when there's just one locale

When there's just one locale, showing the "Remove" menu and the
drag handle is confusing to the user since nothing can happen if
they try to use them: the drag simply won't happen, and if they
go through the delete process, we give them an error.

Bug: 26730336
Change-Id: Ie219dd9b3d653272b325d7af01aba205a58cd472