Roll src/third_party/webrtc 63ada787b5bc..254d3db59ad9 (3 commits)

https://webrtc.googlesource.com/src.git/+log/63ada787b5bc..254d3db59ad9


git log 63ada787b5bc..254d3db59ad9 --date=short --no-merges --format='%ad %ae %s'
2018-11-06 tzik@chromium.org Add missing #include to absl/memory/memory.h from audio_encoder_cng.cc
2018-11-06 kron@webrtc.org Add HdrMetadata to VideoFrame
2018-11-06 eladalon@webrtc.org Remove unused member variable - RTCPSender::using_nack_


Created with:
  gclient setdep -r src/third_party/webrtc@254d3db59ad9

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.

CQ_INCLUDE_TRYBOTS=luci.chromium.try:linux_chromium_archive_rel_ng;luci.chromium.try:mac_chromium_archive_rel_ng

BUG=chromium:752720,chromium:None
TBR=webrtc-chromium-sheriffs-robots@google.com

Change-Id: I4dce8a21814d711bde82c662ead9f9614ac3269e
Reviewed-on: https://chromium-review.googlesource.com/c/1319378Reviewed-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@{#605667}

DEPS

@@ -1161,7 +1161,7 @@ deps = {
     Var('chromium_git') + '/external/khronosgroup/webgl.git' + '@' + '0d55c887e92b645f6effe753528323ab2ffd94c2',
 
   'src/third_party/webrtc':
-    Var('webrtc_git') + '/src.git' + '@' + '63ada787b5bcebbf6573fb6745181c776c755f75',
+    Var('webrtc_git') + '/src.git' + '@' + '254d3db59ad963f347ebc3123fbb564d2d894af1',
 
   'src/third_party/xdg-utils': {
       'url': Var('chromium_git') + '/chromium/deps/xdg-utils.git' + '@' + 'd80274d5869b17b8c9067a1022e4416ee7ed5e0d',