autoroller into chromium setup

[Mike Frysinger]

FYI i setup an autoroller for breakpad into chromium DEPS.  historically this was a manual process, but it meant we would do it infrequently, and in large batches, and any regressions that slipped in would cause a longer turnaround time.  hopefully this should only improve our lives :).

not directly related, but i'm also setting up LSS->chromium & LSS->breakpad.

-mike