Reland "Don't download PESQ and POLQA in the low_bandwidth_audio_test.py script."
Reland "Don't download PESQ and POLQA in the low_bandwidth_audio_test.py script."

This is a reland of f4898a650954691d79bbc146d5b454fb5e67ec47
Original change's description:
> Don't download PESQ and POLQA in the low_bandwidth_audio_test.py script.
> 
> They should've been downloaded already.
> 
> NOTRY=True
> 
> Bug: chromium:755660
> Change-Id: I8ecb355f06026a38bd9377633e2be6c55d7c6452
> Reviewed-on: https://webrtc-review.googlesource.com/5620
> Commit-Queue: Edward Lemur <d05609f027dc667cc37492b1dc1bdea5d60fa82a@webrtc.org>
> Reviewed-by: Oleh Prypin <oprypin@webrtc.org>
> Reviewed-by: Henrik Kjellander <60c11d3e646624f25a02b88f51d51ca6b7ff7c72@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#20109}

No-Try: true
Bug: chromium:755660
Change-Id: I391130545eee5d4928101f87ac4a4e0945d665a1
Reviewed-on: https://webrtc-review.googlesource.com/6380
Commit-Queue: Edward Lemur <d05609f027dc667cc37492b1dc1bdea5d60fa82a@webrtc.org>
Reviewed-by: Henrik Kjellander <60c11d3e646624f25a02b88f51d51ca6b7ff7c72@webrtc.org>
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#20140}
ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc