Update a bibitem label also when it is emptied.

It is valid for a label to be empty, but up to now the bibliography
information was not updated when a label was emptied.

src/insets/InsetBibitem.cpp

@@ -166,13 +166,13 @@ void InsetBibitem::doDispatch(Cursor & cur, FuncRequest & cmd)
 						if (label[previous] != '{')
 							label.replace(pos, 1, lbrace + brackets_escape[k] + rbrace);
 				}
+		}
 
 		if (old_label != label) {
 			p["label"] = label;
 			cur.forceBufferUpdate();
 			buffer().invalidateBibinfoCache();
 		}
-		}
 
 		setParam("label", p["label"]);
 		if (p["key"] != old_key) {

status.20x

@@ -67,6 +67,8 @@ What's new
 
 - Handle correctly undo when a branch is (de)activated.
 
+- Update a bibliography entry's label also when it is emptied.
+
 
 * DOCUMENTATION AND LOCALIZATION