Roll WebRTC 17923:17979 (29 commits)

Changes: https://chromium.googlesource.com/external/webrtc/trunk/webrtc.git/+log/5515dcd..cbb47fe

$ git log 5515dcd..cbb47fe --date=short --no-merges --format=%ad %ae %s
2017-05-02 perkj@webrtc.org Revert of Extract iOS SDK helpers to separate target. (patchset #3 id:40001 of https://codereview.webrtc.org/2849823002/ )
2017-05-02 nisse@webrtc.org Revert of Delete deprecated and transitional stuff related to video frame refactoring. (patchset #1 id:1 of https://codereview.webrtc.org/2852303002/ )
2017-05-02 ossu@webrtc.org Injectable audio encoders: Moved audio encoder, factory and builtin factory to api/.
2017-05-02 pbos@webrtc.org Remove unused 'last_key_frame_picture_id' field.
2017-05-02 perkj@webrtc.org Revert of Relanding: Fixing crash that can occur if signal is modified while firing. (patchset #4 id:60001 of https://codereview.webrtc.org/2846593005/ )
2017-05-02 nisse@webrtc.org Reland of Delete deprecated and transitional stuff related to video frame refactoring. (patchset #1 id:1 of https://codereview.webrtc.org/2845333002/ )
2017-05-02 kjellander@webrtc.org Extract iOS SDK helpers to separate target.
2017-05-02 denicija@webrtc.org Add unit test class for RTCCameraVideoCapturer.
2017-05-02 pbos@webrtc.org Extract TL config to VP8 libvpx flag conversion.
2017-05-02 brandtr@webrtc.org Delete dead code VP8EncoderImpl::UpdateCodecFrameSize.
2017-05-02 terelius@webrtc.org When receiving an RTCP packet containing feedback about multiple RTP packets, we currently check for bandwidth overuse once for every RTP packet.
2017-05-02 ilnik@webrtc.org Fix video_loopback to work with -duration flag: add missing ntp_timestamp to frames
2017-05-02 oprypin@webrtc.org Disable video quality test due to unexpected failures
2017-05-01 deadbeef@webrtc.org Relanding: Fixing crash that can occur if signal is modified while firing.
2017-05-01 deadbeef@webrtc.org Disable CpuTimeTest on instrumented builds.
2017-04-29 deadbeef@webrtc.org Revert of Fixing crash that can occur if signal is modified while firing. (patchset #3 id:40001 of https://codereview.webrtc.org/2846593005/ )
2017-04-29 deadbeef@webrtc.org Fixing crash that can occur if signal is modified while firing.
2017-04-29 deadbeef@webrtc.org Fixing sigslot copy constructors.
2017-04-28 zijiehe@chromium.org Allow Windows to return a monitor out of the first quadrant
2017-04-28 zijiehe@chromium.org Revert of Allow Windows to return a monitor out of the first quadrant (patchset #2 id:60001 of https://codereview.chromium.org/2848443004/ )
2017-04-28 zijiehe@chromium.org Allow Windows to return a monitor out of the first quadrant
2017-04-28 terelius@webrtc.org Create tool to print statistics about the file size usage of an RTC event log.
2017-04-28 ossu@webrtc.org Hooked up Opus CBR support when configured manually or through an SdpAudioFormat.
2017-04-28 nisse@webrtc.org Delete RawVideoType enum, use the VideoType enum instead.
2017-04-28 nisse@webrtc.org Revert of Delete deprecated and transitional stuff related to video frame refactoring. (patchset #17 id:320001 of https://codereview.webrtc.org/2622263002/ )
2017-04-28 nisse@webrtc.org Delete deprecated and transitional stuff related to video frame refactoring.
2017-04-28 mbonadei@webrtc.org Reland of Enable GN check for webrtc/base (patchset #3 id:230001 of https://codereview.webrtc.org/2838683002/ )
2017-04-28 philipel@webrtc.org Reject re-inserting already decoded frames into FrameBuffer2.
2017-04-28 brandtr@webrtc.org Update FlexFEC field trial string in AppRTCMobile Android.

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

Review-Url: https://codereview.chromium.org/2854833003
Cr-Commit-Position: refs/heads/master@{#468646}

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' + '@' + '5515dcd0567c4df4f3cdd9487f4f1556e558dfc3', # commit position 17923
+    Var('chromium_git') + '/external/webrtc/trunk/webrtc.git' + '@' + 'cbb47fe81a77e7d882b2fc8c0412cbfb0d403d21', # commit position 17979
 
   'src/third_party/openmax_dl':
     Var('chromium_git') + '/external/webrtc/deps/third_party/openmax.git' + '@' +  Var('openmax_dl_revision'),