Confirmed that revision b34c0f6877af54e8bdd6052bf8934dd46a3b5899 is to blame.

Crash in ChromotingJniRuntime::ConnectToHost() on this line:
DCHECK(ui_task_runner()->BelongsToCurrentThread());

From adb logcat:

03-18 18:02:15.197  6884  6884 F chromium: [0318/180215:FATAL:ref_counted.h(315)] Assert failed: ptr_ != __null. 
03-18 18:02:15.197  6884  6884 F chromium: #00 0xa1685e85 /data/app/org.chromium.chromoting-1/lib/arm/libremoting_client_jni.so+0x009c3e85
03-18 18:02:15.197  6884  6884 F chromium: #01 0xa0d80ba9 /data/app/org.chromium.chromoting-1/lib/arm/libremoting_client_jni.so+0x000beba9
03-18 18:02:15.197  6884  6884 F chromium: #02 0xa0d83d95 /data/app/org.chromium.chromoting-1/lib/arm/libremoting_client_jni.so+0x000c1d95
03-18 18:02:15.197  6884  6884 F chromium: #03 0xa0d83f99 /data/app/org.chromium.chromoting-1/lib/arm/libremoting_client_jni.so+0x000c1f99
03-18 18:02:15.197  6884  6884 F chromium: #04 0xa2593c89 /data/app/org.chromium.chromoting-1/oat/arm/base.odex+0x00734c89
03-18 18:02:15.197  6884  6884 F chromium: 
03-18 18:02:15.198  6884  6884 F libc    : Fatal signal 6 (SIGABRT), code -6 in tid 6884 (mium.chromoting)
03-18 18:02:15.299  1402  1402 F DEBUG   : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
03-18 18:02:15.299  1402  1402 F DEBUG   : Build fingerprint: 'google/razor/flo:6.0.1/MMB29W/2641372:user/release-keys'
03-18 18:02:15.299  1402  1402 F DEBUG   : Revision: '0'
03-18 18:02:15.299  1402  1402 F DEBUG   : ABI: 'arm'
03-18 18:02:15.299  1402  1402 F DEBUG   : pid: 6884, tid: 6884, name: mium.chromoting  >>> org.chromium.chromoting <<<
03-18 18:02:15.299  1402  1402 F DEBUG   : signal 6 (SIGABRT), code -6 (SI_TKILL), fault addr --------
03-18 18:02:15.324  1402  1402 F DEBUG   : Abort message: '[0318/180215:FATAL:ref_counted.h(315)] Assert failed: ptr_ != __null. 
03-18 18:02:15.324  1402  1402 F DEBUG   : #00 0xa1685e85 /data/app/org.chromium.chromoting-1/lib/arm/libremoting_client_jni.so+0x009c3e85
03-18 18:02:15.324  1402  1402 F DEBUG   : #01 0xa0d80ba9 /data/app/org.chromium.chromoting-1/lib/arm/libremoting_client_jni.so+0x000beba9
03-18 18:02:15.324  1402  1402 F DEBUG   : #02 0xa0d83d95 /data/app/org.chromium.chromoting-1/lib/arm/libremoting_client_jni.so+0x000c1d95

From gdb:

Program received signal SIGBUS, Bus error.
DebugBreak () at ../../base/debug/debugger_posix.cc:221
221	    DEBUG_BREAK_ASM();
(gdb) bt
#0  DebugBreak () at ../../base/debug/debugger_posix.cc:221
#1  base::debug::BreakDebugger () at ../../base/debug/debugger_posix.cc:248
#2  0xa1685fda in logging::LogMessage::~LogMessage (this=0xbeb503f4, __in_chrg=<optimized out>) at ../../base/logging.cc:737
#3  0xa0d80baa in scoped_refptr<remoting::AutoThreadTaskRunner>::operator-> (this=0xbeb504d0) at ../../base/memory/ref_counted.h:315
#4  0xa0d83d96 in remoting::ChromotingJniRuntime::ConnectToHost (this=this@entry=0xacbad3b0, username=..., auth_token=..., host_jid=..., 
    host_id=..., host_pubkey=..., pairing_id=..., pairing_secret=..., capabilities=..., flags=...)
    at ../../remoting/client/jni/chromoting_jni_runtime.cc:265
#5  0xa0d83f9a in Connect (clazz=..., flags=..., capabilities=..., pairSecret=..., pairId=..., hostPubkey=..., hostId=..., hostJid=..., 
    authToken=..., username=..., env=0xb4d56b40) at ../../remoting/client/jni/chromoting_jni_runtime.cc:93
#6  remoting::Java_org_chromium_chromoting_jni_JniInterface_nativeConnect (env=0xb4d56b40, jcaller=<optimized out>, 
    username=<optimized out>, authToken=<optimized out>, hostJid=0xbeb506c8, hostId=0xbeb506cc, hostPubkey=0xbeb506d0, pairId=0xbeb506d4, 
    pairSecret=0xbeb506d8, capabilities=0xbeb506dc, flags=0xbeb506e0)
    at gen/remoting/android/jni_headers/remoting/jni/JniInterface_jni.h:98
#7  0xa2593c8a in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)