Revert 246894 "Wire up AGC to the MediaStreamAudioProcessor."

Revert 246894 "Wire up AGC to the MediaStreamAudioProcessor."

It seems to have broken this test:
[----------] 1 test from AudioStreamHandlerTest
[ RUN      ] AudioStreamHandlerTest.ConsecutivePlayRequests
../../media/base/android/media_source_player_unittest.cc:1665: Failure
Expected: (first_job) != (second_job), actual: 0x766d4210 vs 0x766d4210
[  FAILED  ] MediaSourcePlayerTest.VideoConfigChangeContinuesAcrossSeek (125 ms)
[ RUN      ] MediaSourcePlayerTest.SeekToThenReleaseThenStart
[       OK ] MediaSourcePlayerTest.SeekToThenReleaseThenStart (82 ms)
[----------] 8 tests from MediaSourcePlayerTest (590 ms total)

> Wire up AGC to the MediaStreamAudioProcessor.
> 
> This CL enables the AGC in the processor based on the constraints, and also trigger SetVolume() in the capturer if the AGC tries to adjust the volume.
> 
> There are also some small changes in the MediaStreamAudioProcessor and its unittest.
> 
> BUG=264611
> TEST= content_unittest --gtest_filter="*MediaStreamAudioProcessor*"
> 
> Review URL: https://codereview.chromium.org/141513006

TBR=xians@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=246905

[MAD, 2014-01-24 16:43:29]

Committed patchset #1 manually as r246905 (tree was closed).