talk/media/webrtc/webrtcvoiceengine: Delay Agnostic AEC should not override HW-AEC
talk/media/webrtc/webrtcvoiceengine: Delay Agnostic AEC should not override HW-AEC

In https://webrtc-codereview.appspot.com/48699004/ I made the audio option delay_agnostic_aec override HW-AEC if such exists. That is not an expected behavior and is fixed in this CL.

In addition we now check if EnableBuiltInAEC() was successful before disabling the SW-AEC. This revealed a bug in that return value, also fixed here.

BUG=4472
R=henrika@webrtc.org, perkj@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/47969004

Cr-Original-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#8936}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 1d83f1e89f3e54b38d49ff877c763d0ac52fdb8b

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