Roll WebRTC from a6c70741e76f to 3c9ae1fd8fb7 (1 revision)

https://webrtc.googlesource.com/src.git/+log/a6c70741e76f..3c9ae1fd8fb7

2020-06-02 hta@webrtc.org Adds fix for closing a prenegotiated DC without sending data.

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/webrtc-chromium-autoroll
Please CC webrtc-chromium-sheriffs-robots@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+doc/master/autoroll/README.md

Bug: None
Tbr: webrtc-chromium-sheriffs-robots@google.com
Change-Id: Ia3f824210022436e715304a5a149e2b9cc40b69a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2227158Reviewed-by: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Commit-Queue: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#774388}

DEPS

@@ -1448,7 +1448,7 @@ deps = {
   },
 
   'src/third_party/webrtc':
-    Var('webrtc_git') + '/src.git' + '@' + 'a6c70741e76f2278bde5c7eab9d37984fe41dcf0',
+    Var('webrtc_git') + '/src.git' + '@' + '3c9ae1fd8fb7aae488eb24d4158dd9d71fdf1f2d',
 
   'src/third_party/libgifcodec':
      Var('skia_git') + '/libgifcodec' + '@'+  Var('libgifcodec_revision'),