commit 5b1477839d8569291b88dfe950089d0ebf34bc8f
author Henrik Boström <hbos@webrtc.org> Tue Dec 04 10:25:05 2018
committer Commit Bot <commit-bot@chromium.org> Wed Dec 05 09:53:21 2018
tree 0d54a6320976958f938e12225ea6e8d4a0af4dc1
parent e5e36ddc400fc660c72601f63739615446659a83

[Unified Plan] If "a=msid" is missing, create default stream.

Prior to this CL, if the "a=msid" attribute was missing it was treated
the same as if "no streams" were explicitly signaled (a=msid:-); the
receivers would not be associated with any streams.

In order to support legacy endpoints that don't recognize "a=msid" that
assume the Plan B behavior of a stream being created anyway, this CL
creates a stream with a random ID in such cases. For background, see
https://github.com/web-platform-tests/wpt/pull/14054.

Bug: chromium:907508
Change-Id: I9d9dd0e4ba8f9941f8652f4d7873adc560777cd9
Reviewed-on: https://webrtc-review.googlesource.com/c/112900
Reviewed-by: Seth Hampson <shampson@webrtc.org>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25901}

pc/webrtcsdp_unittest.cc

diff --git a/pc/webrtcsdp_unittest.cc b/pc/webrtcsdp_unittest.cc
index d8b6811..8a3c28f 100644
--- a/pc/webrtcsdp_unittest.cc
+++ b/pc/webrtcsdp_unittest.cc
@@ -2501,6 +2501,8 @@
   EXPECT_TRUE(SdpDeserialize(sdp_without_msid, &jdesc));
   // Verify
   EXPECT_TRUE(CompareSessionDescription(jdesc_, jdesc));
+  EXPECT_FALSE(jdesc.description()->msid_signaling() &
+               ~cricket::kMsidSignalingSsrcAttribute);
 }
 
 TEST_F(WebRtcSdpTest, DeserializeSessionDescriptionWithExtmapAllowMixed) {
@@ -3497,6 +3499,9 @@
                              &deserialized_description));
 
   EXPECT_TRUE(CompareSessionDescription(jdesc_, deserialized_description));
+  EXPECT_EQ(cricket::kMsidSignalingMediaSection |
+                cricket::kMsidSignalingSsrcAttribute,
+            deserialized_description.description()->msid_signaling());
 }
 
 // Tests the serialization of a Unified Plan SDP that is compatible for both