Always call back from mainloop in g_daemon_file_find_enclosing_mount_async
Always call back from mainloop in g_daemon_file_find_enclosing_mount_async

On cache hit g_daemon_file_find_enclosing_mount_async would immediately
call the callback function which breaks the aysnc-pattern contract.
Fixes bug #609002.

halfline/gvfs,philipl/gvfs,xkahn/gvfs-cmis,gicmo/gvfs,philipl/gvfs,xkahn/gvfs-cmis,xkahn/gvfs-cmis,cpatulea/gvfs,halfline/gvfs,cpatulea/gvfs,gicmo/gvfs,gicmo/gvfs,xkahn/gvfs-cmis,halfline/gvfs,philipl/gvfs,gicmo/gvfs