Comment 2 for bug 1581653

StacktraceTop:
 gtk_tree_store_get_value (tree_model=0x23d6b00, iter=<optimized out>, column=0, value=0x7ffd3231cb60) at /build/gtk+3.0-lL7YRg/gtk+3.0-3.18.9/./gtk/gtktreestore.c:657
 gtk_tree_model_get_valist (tree_model=tree_model@entry=0x23d6b00, iter=iter@entry=0x7ffd3231cd10, var_args=var_args@entry=0x7ffd3231cc10) at /build/gtk+3.0-lL7YRg/gtk+3.0-3.18.9/./gtk/gtktreemodel.c:1795
 gtk_tree_model_get (tree_model=tree_model@entry=0x23d6b00, iter=iter@entry=0x7ffd3231cd10) at /build/gtk+3.0-lL7YRg/gtk+3.0-3.18.9/./gtk/gtktreemodel.c:1759
 gcm_prefs_device_changed_cb (device=0x2475630, prefs=0x23ed260) at cc-color-panel.c:1890
 _g_closure_invoke_va () from /tmp/apport_sandbox_OZfgbi/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0