libtracker-client: Fix memleak, unref DBusPendingCall missing in notify callback
libtracker-client: Fix memleak, unref DBusPendingCall missing in notify callback

hoheinzollern/tracker,outofbits/tracker,outofbits/tracker,outofbits/tracker,hoheinzollern/tracker,hoheinzollern/tracker,outofbits/tracker,outofbits/tracker,hoheinzollern/tracker,outofbits/tracker,hoheinzollern/tracker,hoheinzollern/tracker,outofbits/tracker,hoheinzollern/tracker