Roll src/third_party/webrtc/ 4c9b3c840..19aab2ee7 (16 commits)

https://webrtc.googlesource.com/src.git/+log/4c9b3c840df3..19aab2ee7c6b

$ git log 4c9b3c840..19aab2ee7 --date=short --no-merges --format='%ad %ae %s'

Created with:
  roll-dep src/third_party/webrtc
BUG=chromium:None,chromium:812974,chromium:827080,chromium:None,chromium:794210,chromium:825524


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

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.


CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_chromium_archive_rel_ng;master.tryserver.chromium.mac:mac_chromium_archive_rel_ng;master.tryserver.chromium.win:win-msvc-dbg
TBR=webrtc-chromium-sheriffs-robots@google.com

Change-Id: If6b26fb8305b2e0d8c796358684d52a63d181a77
Reviewed-on: https://chromium-review.googlesource.com/999352Reviewed-by: webrtc-chromium-autoroll <webrtc-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Commit-Queue: webrtc-chromium-autoroll <webrtc-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#548696}

DEPS

@@ -876,7 +876,7 @@ deps = {
     Var('chromium_git') + '/external/khronosgroup/webgl.git' + '@' + 'da5abe6e9bae583e4ae73aa553547fcaa637d099',
 
   'src/third_party/webrtc':
-    Var('webrtc_git') + '/src.git' + '@' + '4c9b3c840df3baf5145d73ecb994ba24b87908c7', # commit position 21742
+    Var('webrtc_git') + '/src.git' + '@' + '19aab2ee7c6b0d8c31f530c7a99250080c6c4bf2', # commit position 21742
 
   'src/third_party/xdg-utils': {
       'url': Var('chromium_git') + '/chromium/deps/xdg-utils.git' + '@' + 'd80274d5869b17b8c9067a1022e4416ee7ed5e0d',