Roll src/third_party/webrtc 8e998f17e0ce..be99ee8f17f9 (3 commits)

https://webrtc.googlesource.com/src.git/+log/8e998f17e0ce..be99ee8f17f9

git log 8e998f17e0ce..be99ee8f17f9 --date=short --first-parent --format='%ad %ae %s'
2020-01-30 terelius@webrtc.org Add more options for tuning the RobustThroughputEstimator through field trial.
2020-01-30 srte@webrtc.org Revert "Inlines NullAudioPoller functionality into AudioState class."
2020-01-30 srte@webrtc.org Inlines NullAudioPoller functionality into AudioState class.

Created with:
  gclient setdep -r src/third_party/webrtc@be99ee8f17f9

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/+/master/autoroll/README.md

Bug: None
Tbr: webrtc-chromium-sheriffs-robots@google.com
Change-Id: I65b4b67b289d7136b80864653e7e6a8c0ff4f2ab
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2031692Reviewed-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@{#737066}

DEPS

@@ -1494,7 +1494,7 @@ deps = {
     Var('chromium_git') + '/external/github.com/gpuweb/cts.git' + '@' + 'ec18cc3262922e7dcdbe70243c6f40606f979144',
 
   'src/third_party/webrtc':
-    Var('webrtc_git') + '/src.git' + '@' + '8e998f17e0ce24d68e9d68efa78c1f390bf3af47',
+    Var('webrtc_git') + '/src.git' + '@' + 'be99ee8f17f93e06c81e3deb4897dfa8253d3211',
 
   'src/third_party/libgifcodec':
      Var('skia_git') + '/libgifcodec' + '@'+  Var('libgifcodec_revision'),