Have the "update_depot_tools" script also do a CIPD tool sync. This will
ensure that users and systems have access to tooling at sync-time rather
than just-in-time loading them at execution time.

Update the tool boostraps to suppress any sort of syncing logic, if it
does happen. This will ensure that users who execute the tools don't se
unexpected output.

BUG=None
TEST=local
  - Tested on Mac and Windows.

R=dpranke@chromium.org, iannucci@chromium.org

Change-Id: I8efce8c73cc4e82ffdf5067ba9b917119a81e843
Reviewed-on: https://chromium-review.googlesource.com/581494
Commit-Queue: Daniel Jacques <dnj@chromium.org>
Reviewed-by: Robbie Iannucci <iannucci@chromium.org>