Add document metadata property. Expose the filename.

lib/python/_sugar.override

@@ -179,6 +179,26 @@ _wrap_sugar_cairo_surface_from_gdk_pixbuf(PyGObject *self, PyObject *args, PyObj
     return PycairoSurface_FromSurface(surface, NULL);
 }
 %%
+override-slot SugarBrowserMetadata.tp_getattr
+static PyObject *
+_wrap_sugar_browser_metadata_tp_getattr(PyObject *self, char *attr)
+{
+    SugarBrowserMetadata *metadata = pyg_boxed_get(self, SugarBrowserMetadata);
+
+    if (!strcmp(attr, "__members__"))
+        return Py_BuildValue("[s]", "filename");
+    else if (!strcmp(attr, "filename")) {
+        if (metadata->filename) {
+            return PyString_FromString(metadata->filename);
+        } else {
+            Py_INCREF(Py_None);
+            return Py_None;
+        }
+    }
+
+    return NULL;
+}
+%%
 override-slot SugarBrowserEvent.tp_getattr
 static PyObject *
 _wrap_sugar_browser_event_tp_getattr(PyObject *self, char *attr)