gio-2.0: Fix uint8[]/char** types for contents parameters for g_file_[load|replace]_contents()

https://bugzilla.gnome.org/show_bug.cgi?id=710867
glib-2.0: Fix type of g_hash_table_iter_next() parameters to always be gpointer

https://bugzilla.gnome.org/show_bug.cgi?id=710868