Roll WebRTC from 2671dac29c27 to 4ab61cb9b449 (1 revision)

https://webrtc.googlesource.com/src.git/+log/2671dac29c27..4ab61cb9b449

2020-05-19 sprang@webrtc.org Optionally allows TaskQueuePacedSender to coalesce send events.

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: Ib9b110ca8f1263d4133d3eca60edb8d787d850fb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2209552Reviewed-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@{#770342}

DEPS

@@ -1453,7 +1453,7 @@ deps = {
   },
 
   'src/third_party/webrtc':
-    Var('webrtc_git') + '/src.git' + '@' + '2671dac29c27d033d14a79708e9a2b9b2b66b8d1',
+    Var('webrtc_git') + '/src.git' + '@' + '4ab61cb9b4499a5e92d29abf5c0df90ca7fdc95c',
 
   'src/third_party/libgifcodec':
      Var('skia_git') + '/libgifcodec' + '@'+  Var('libgifcodec_revision'),