Android NativeCall crashes on Join

Log below:

02-04 19:24:12.171 21791-21791/? W/Zygote: mz_is_rooted false
02-04 19:24:12.171 21791-21791/? I/art: Late-enabling -Xcheck:jni
02-04 19:24:12.221 21791-21805/? I/art: Debugger is no longer active
02-04 19:24:12.261 21791-21791/? I/InstantRun: Instant Run Runtime started. Android package is com.ericsson.research.owr.examples.nativecall, real application class is null.
02-04 19:24:12.581 21791-21818/? I/OpenGLRenderer: Initialized EGL, version 1.4
02-04 19:24:40.751 21791-22297/com.ericsson.research.owr.examples.nativecall I/System.out: httpget:http://demo.openwebrtc.org/stoc/24ade3bc072/f9rk32mk
02-04 19:24:40.751 21791-21816/com.ericsson.research.owr.examples.nativecall I/OpenWebRTC: [435]: JNI: successfully attached to thread
02-04 19:24:40.761 21791-21791/com.ericsson.research.owr.examples.nativecall W/libOpenSLES: Leaving Object::GetInterface (SL_RESULT_FEATURE_UNSUPPORTED)
02-04 19:24:41.131 21791-22297/com.ericsson.research.owr.examples.nativecall I/System.out: >doSendRequest
02-04 19:24:41.131 21791-22297/com.ericsson.research.owr.examples.nativecall I/System.out:

Start with the Join failure and the stack trace in NativeCallExampleActivity.java at line 344, then follow the signaling flow through SignalingChannel.java at lines 95 and 121. Check how the SSLPeerUnverifiedException leads to onDisconnect and verify that Join no longer crashes with a null RtcSession; reproduce the scenario to confirm the completed behavior.

Written by the indexing model from the issue text.