Roll src/third_party/webrtc a0b52b570853..93d4c10ffccc (5 commits)

https://webrtc.googlesource.com/src.git/+log/a0b52b570853..93d4c10ffccc

git log a0b52b570853..93d4c10ffccc --date=short --no-merges --format='%ad %ae %s'
2019-08-20 kthelgason@webrtc.org Declare references as constant in the metal renderers.
2019-08-20 nisse@webrtc.org RTCError as return type for PeerConnectionInterface::SetConfiguration
2019-08-20 qingsi@webrtc.org Sanitize the address field of peer-reflexive remote candidates.
2019-08-20 chromium-webrtc-autoroll@webrtc-ci.iam.gserviceaccount.com Roll chromium_revision 21d23ea5..5a34954f (688221:688384)
2019-08-19 steveanton@webrtc.org Remove jeroendb@webrtc.org from OWNERS

Created with:
  gclient setdep -r src/third_party/webrtc@93d4c10ffccc

The AutoRoll server is located here: https://autoroll.skia.org/r/webrtc-chromium-autoroll

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

If the roll is causing failures, please contact the current sheriff, who should
be CC'd on the roll, and stop the roller if necessary.


TBR=webrtc-chromium-sheriffs-robots@google.com

Bug: chromium:None,chromium:968161,chromium:None,chromium:None
Change-Id: Ifa8e5e4b9e1a2ed70dfe51f83b029f15a99c38e6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1761704Reviewed-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@{#688477}

DEPS

@@ -1391,7 +1391,7 @@ deps = {
     Var('chromium_git') + '/external/khronosgroup/webgl.git' + '@' + 'abaae129d9a0c6e1e092067e0b105475df43352e',
 
   'src/third_party/webrtc':
-    Var('webrtc_git') + '/src.git' + '@' + 'a0b52b5708534943aa66bef724c438244cc84eac',
+    Var('webrtc_git') + '/src.git' + '@' + '93d4c10ffccc2faf2e38bab74ba14414751bae91',
 
   'src/third_party/xdg-utils': {
       'url': Var('chromium_git') + '/chromium/deps/xdg-utils.git' + '@' + 'd80274d5869b17b8c9067a1022e4416ee7ed5e0d',