It is unnecessary to include the build hooks implementation because we
don't use them. It was also causing errors because the interface the
class implements is not included in the AAR.
Also removes comments about re-enabling build hooks because it has grown
into something very Chromium specific and it is unlikely that we want to
re-enable them.
Bug: webrtc:8964, webrtc:8168
Change-Id: Ia95af13e90a5511554305d2688ced820e9914beb
Reviewed-on: https://webrtc-review.googlesource.com/61302
Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
Commit-Queue: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22386}
b9f4bf29d0