Reason for revert:
This CL are breaking some of the Android buildbots in Chromium.
The CL will need be be revised to exclude the Android platform.
Original issue's description:
> Added a bitexactness test for the gain controller in the audio processing module.
>
> BUG=webrtc:5339
>
> Committed: https://crrev.com/a49dc36976da44f3d6d75aed2dcab93fe14fc3a0
> Cr-Commit-Position: refs/heads/master@{#12124}
TBR=henrik.lundin@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:5339
Review URL: https://codereview.webrtc.org/1829323002
Cr-Commit-Position: refs/heads/master@{#12127}