Removed double-special-casing of ISAC in libjingle and WebRtcVoE.

webrtc/media/engine/webrtcvoiceengine.cc

 /*
  *  Copyright (c) 2004 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 353 matching lines @@
           voe_codec.pltype = in.id;
 
           // Set bitrate if specified.
           if (multi_rate && in.bitrate != 0) {
             voe_codec.rate = in.bitrate;
           }
 
           // Reset G722 sample rate to 16000 to match WebRTC.
           MaybeFixupG722(&voe_codec, 16000);
 
-          // Apply codec-specific settings.
-          if (IsCodec(codec, kIsacCodecName)) {
-            // If ISAC and an explicit bitrate is not specified,

[ossu, 2017/01/19 16:48:48]

After removing the rate setting code here and in webrtcsdp.cc, I ran through
*_tests and *_unittests with a CHECK here, that ensured voe_codec.rate was never
zero. It didn't trigger.
I expect zero is not a usable value for ISAC, since we previously had to change
it to -1. (This is, in it self, a bit strange).

[kwiberg-webrtc, 2017/01/23 15:18:11]

So in other words, in.bitrate was always -1 or >=1 here, causing the deleted
code to have no effect?

[ossu, 2017/01/23 15:33:18]

Yes, the block in webrtcsdp.cc ensured that we didn't set bitrate to -1. It set
in.bitrate to match the values that voe_codec.rate would already have been set
to by line 368, above.

[kwiberg-webrtc, 2017/01/23 15:38:40]

Acknowledged.

-            // enable auto bitrate adjustment.
-            voe_codec.rate = (in.bitrate > 0) ? in.bitrate : -1;
-          }
           *out = voe_codec;
         }
         return true;
       }
     }
     return false;
   }
 
   static bool IsCodecMultiRate(const webrtc::CodecInst& codec) {
     for (size_t i = 0; i < arraysize(kCodecPrefs); ++i) {
@@ skipping 2321 matching lines @@
   RTC_DCHECK(worker_thread_checker_.CalledOnValidThread());
   const auto it = send_streams_.find(ssrc);
   if (it != send_streams_.end()) {
     return it->second->channel();
   }
   return -1;
 }
 }  // namespace cricket
 
 #endif  // HAVE_WEBRTC_VOICE