LastfmRequest: Fix crash after response timeout (bgo#684792)
LastfmRequest: Fix crash after response timeout (bgo#684792)

Dynalon/banshee-osx,Carbenium/banshee,arfbtwn/banshee,babycaseny/banshee,dufoli/banshee,GNOME/banshee,GNOME/banshee,Dynalon/banshee-osx,arfbtwn/banshee,Carbenium/banshee,GNOME/banshee,arfbtwn/banshee,dufoli/banshee,GNOME/banshee,arfbtwn/banshee,Dynalon/banshee-osx,Dynalon/banshee-osx,arfbtwn/banshee,Dynalon/banshee-osx,GNOME/banshee,stsundermann/banshee,arfbtwn/banshee,Carbenium/banshee,Dynalon/banshee-osx,dufoli/banshee,arfbtwn/banshee,ixfalia/banshee,babycaseny/banshee,stsundermann/banshee,Dynalon/banshee-osx,stsundermann/banshee,arfbtwn/banshee,Carbenium/banshee,dufoli/banshee,ixfalia/banshee,babycaseny/banshee,ixfalia/banshee,babycaseny/banshee,stsundermann/banshee,ixfalia/banshee,GNOME/banshee,babycaseny/banshee,babycaseny/banshee,dufoli/banshee,GNOME/banshee,ixfalia/banshee,babycaseny/banshee,GNOME/banshee,ixfalia/banshee,dufoli/banshee,dufoli/banshee,stsundermann/banshee,Dynalon/banshee-osx,dufoli/banshee,stsundermann/banshee,stsundermann/banshee,ixfalia/banshee,ixfalia/banshee,stsundermann/banshee,babycaseny/banshee,Carbenium/banshee,Carbenium/banshee