Bug 1043186 - Part 1: Add a nsINfcPeerEventListener. r=dimi
Bug 1043186 - Part 2: onpeerlost should be fired to correct target. r=dimi
Bug 1043186 - Part 3: return cached NFCPeer if session matches.
Bug 1043186 - Part 4: Add throw in MozNFCPeer. r=smaug, dimi