Various extensions cleanup

Removes some unused arguments, corrects comments, fixes up includes

Change-Id: I908530b5c827c611eafb4403a6e674d25a28414b
Reviewed-on: https://chromium-review.googlesource.com/912275
Reviewed-by: Karan Bhatia <karandeepb@chromium.org>
Commit-Queue: Michael Giuffrida <michaelpg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#535945}
9 files changed