If a library is missing, or some other problem causes xpcshell itself to fail, the failure is not detected or reported when running "make xpcshell-tests-remote". It looks like every test passes, but no tests are actually run. I noticed this when running with the adb devicemanager...not sure if it happens with sut or not.

I still haven't had opportunity to investigate this issue properly. However, I notice that SUT returns a return code along with stdout; I am not sure if the xpcshell script is checking that. Also, there is no ADB equivalent, and this bug was reported in an ADB context. With devicemanagerADB, we are at best checking that adb executed. Consider adding "echo $?" to the adb command line to retrieve the last command's return code.

Bugs 728298 and 705192 change the way that xpcshell is launched and monitored, effectively addressing this bug. If xpcshell cannot be launched, crashes, or hangs, the associated test now fails.