Roll WebRTC 19024:19063 (17 commits)

Changes: https://chromium.googlesource.com/external/webrtc/trunk/webrtc.git/+log/beaccf9..2048bc4

$ git log beaccf9..2048bc4 --date=short --no-merges --format=%ad %ae %s
2017-07-17 zstein@webrtc.org Remove default implementation of PeerConnectionInterface::SetBitrate.
2017-07-17 steveanton@webrtc.org Android bindings for ice_regather_interval_range RTCConfiguration option
2017-07-13 zijiehe@google.com Expose IsCurrentSessionSupported() from ScreenCapturerWinDirectx
2017-07-17 minyue@webrtc.org Revert "Prefer external video codecs over internal in SDP"
2017-07-17 tschumim@webrtc.org Don't run NoBandwidthDropAfterDtx test on andriod because it's flaky.
2017-07-17 tschumim@webrtc.org Reimplemeted "Test and fix for huge bwe drop after alr state"
2017-07-16 eladalon@webrtc.org nit: Avoid pointer-to-unique_ptr in RtcEventLogImpl
2017-07-15 tommi@webrtc.org Fix incorrect DCHECK in generic_decoder.cc. When ownership is not external, the decoder pointer should be valid.
2017-07-14 jtteh@webrtc.org Revert of Injectable Obj-C video codecs (patchset #2 id:370001 of https://codereview.webrtc.org/2979983002/ )
2017-07-14 steveanton@webrtc.org Reinstate "iOS - Add iceRegatherIntervalRange."
2017-07-14 steveanton@webrtc.org Reinstate "Add additional check when setting RTCConfiguration"
2017-07-14 steveanton@webrtc.org Reinstate "API for periodically regathering ICE candidates"
2017-07-14 mbonadei@webrtc.org Disabling test on iOS64 debug bot
2017-07-14 tommi@webrtc.org Reland of Make the default ctor of rtc::Thread, protected
2017-07-14 zstein@webrtc.org SignalPacketReceived should pass packet as a pointer instead of a non-const reference.
2017-07-14 zstein@webrtc.org Adding stats that can be used to compute output audio levels as described here https://w3c.github.io/webrtc-stats/#dom-rtcmediastreamtrackstats-totalaudioenergy.
2017-07-14 magjed@webrtc.org Prefer external video codecs over internal in SDP

TBR=
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_chromium_archive_rel_ng;master.tryserver.chromium.mac:mac_chromium_archive_rel_ng

Bug: 
Change-Id: Ic042ed27f7e9d91532f3cbf2b979b76f1b853448
Reviewed-on: https://chromium-review.googlesource.com/575987Reviewed-by: Henrik Andreasson <henrika@chromium.org>
Commit-Queue: Henrik Andreasson <henrika@chromium.org>
Cr-Commit-Position: refs/heads/master@{#487426}

DEPS

@@ -235,7 +235,7 @@ deps = {
     Var('chromium_git') + '/native_client/src/third_party/scons-2.0.1.git' + '@' + '1c1550e17fc26355d08627fbdec13d8291227067',
 
   'src/third_party/webrtc':
-    Var('chromium_git') + '/external/webrtc/trunk/webrtc.git' + '@' + 'beaccf9aa08e8e5dbd06235d60150bbe0e14ce98', # commit position 19024
+    Var('chromium_git') + '/external/webrtc/trunk/webrtc.git' + '@' + '2048bc47c23b16f614fd6ab680b6faa0cf02a2f4', # commit position 19063
 
   'src/third_party/openmax_dl':
     Var('chromium_git') + '/external/webrtc/deps/third_party/openmax.git' + '@' +  Var('openmax_dl_revision'),