Version: 54.0.2840.71 m

CastTransportIPC considers possibility that CastIPCDispatcher::Get() might return null but in such case, it still sends messages to channel_id_ that wasn't initialized...

It should probably:
a) initialize channel id to invalid value (-1)
b) not send constructor and destructor messages (CastHostMsg_New and CastHostMsg_Delete) when channel_id_ is not initialized
c) assert in public methods that channel_id_ is initialized

This "problem" might not be a problem for Chrome in practice if CastIPCDispatcher::Get() is always non-null, but I found it while debugging cast problem in Opera as we had some bits not enabled.