private void removeAssociatedGroups(Collection<FGVertex> groupVertices) {
		for (FGVertex vertex : groupVertices) {
			Iterator<GroupHistoryInfo> iterator = groupHistorySet.iterator();
			for (; iterator.hasNext();) {
				GroupHistoryInfo info = iterator.next();
				if (!info.contains(vertex)) {
					continue;
				}

				//
				// NOTE: this code is setup such that for any given GroupHistoryInfo, if any of
				//       its internal vertices are *moved to a new group*, then the entire history
				//       is removed.  We could do something different, like simply remove the
				// 	     vertex from the history entry.  For now, the current code seems simpler
				//       in that once you alter an 'uncollapsed' group entry, the whole thing
				//       goes away.
				//
				// SUBNOTE: if a vertex is manually removed from an 'uncollapsed' group, then the
				//          history is NOT removed.
				//

				notifyVerticesOfGroupAssociation(info.getVertices(), null);
				iterator.remove();
			}
		}
	}
Any time a vertex is grouped we want to make sure that any previous group affiliations
are removed.

@param groupVertices the new grouping of vertices
Ghidra/Features/FunctionGraph/src/main/java/ghidra/app/plugin/core/functiongraph/graph/FunctionGraph.java