Invalid read in inhibit_suspend_done

[Sebastien Bacher]

Using current trusty, valgrind showed those for one of the greeter sessions

"==3050== Invalid read of size 4
==3050== at 0x47B0022: g_type_check_instance_cast (gtype.c:3997)
==3050== by 0x72874F1: inhibit_suspend_done (gsd-power-manager.c:3277)
==3050== by 0x46680A4: g_simple_async_result_complete (gsimpleasyncresult.c:763)
==3050== by 0x46D7FAC: reply_cb (gdbusproxy.c:2623)
==3050== by 0x46680A4: g_simple_async_result_complete (gsimpleasyncresult.c:763)
==3050== by 0x46CC7A7: g_dbus_connection_call_done (gdbusconnection.c:5498)
==3050== by 0x46680A4: g_simple_async_result_complete (gsimpleasyncresult.c:763)
==3050== by 0x466810A: complete_in_idle_cb (gsimpleasyncresult.c:775)
==3050== by 0x4814C4F: g_idle_dispatch (gmain.c:5319)
==3050== by 0x48180A6: g_main_context_dispatch (gmain.c:3064)
==3050== by 0x4818467: g_main_context_iterate.isra.24 (gmain.c:3734)
==3050== by 0x481876A: g_main_loop_run (gmain.c:3928)
==3050== by 0x425334C: gtk_main (gtkmain.c:1158)
==3050== by 0x804AA29: main (main.c:476)
==3050== Address 0x55e4320 is 248 bytes inside a block of size 268 free'd
==3050== at 0x402AD58: free (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==3050== by 0x481DD2F: g_free (gmem.c:190)
==3050== by 0x483487A: g_slice_free1 (gslice.c:1112)
==3050== by 0x47AEDF0: g_type_free_instance (gtype.c:1932)
==3050== by 0x47912CF: g_object_unref (gobject.c:3125)
==3050== by 0x7289520: gsd_power_plugin_finalize (gsd-power-plugin.c:29)
==3050== by 0x47912C7: g_object_unref (gobject.c:3112)
==3050== by 0x804C478: gnome_settings_plugin_info_finalize (gnome-settings-plugin-info.c:97)
==3050== by 0x47912C7: g_object_unref (gobject.c:3112)
==3050== by 0x4835777: g_slist_foreach (gslist.c:877)
==3050== by 0x804BE53: gnome_settings_manager_stop (gnome-settings-manager.c:337)
==3050== by 0x804ACFF: name_lost_handler (main.c:69)
==3050== by 0x46D4B46: actually_do_call (gdbusnameowning.c:163)
==3050== by 0x46D4C8C: do_call (gdbusnameowning.c:214)
==3050== by 0x4FD63C5: ffi_call_SYSV (sysv.S:65)
==3050== by 0x4FD614A: ffi_call (ffi.c:411)
==3050== by 0x478D308: g_cclosure_marshal_generic (gclosure.c:1445)
==3050== by 0x478CA7D: g_closure_invoke (gclosure.c:768)
==3050== by 0x479F028: signal_emit_unlocked_R (gsignal.c:3551)
==3050== by 0x47A6962: g_signal_emit_valist (gsignal.c:3307)
==3050== by 0x47A6BF2: g_signal_emit (gsignal.c:3363)
==3050== by 0x46C5C99: emit_closed_in_idle (gdbusconnection.c:1385)
==3050== by 0x4814C4F: g_idle_dispatch (gmain.c:5319)
==3050== by 0x48180A6: g_main_context_dispatch (gmain.c:3064)
==3050== by 0x4818467: g_main_context_iterate.isra.24 (gmain.c:3734)
==3050== by 0x481876A: g_main_loop_run (gmain.c:3928)
==3050== by 0x425334C: gtk_main (gtkmain.c:1158)
==3050== by 0x804AA29: main (main.c:476)"