BufferGeometryUtils: Clean up.

examples/js/utils/BufferGeometryUtils.js

@@ -722,6 +722,7 @@ THREE.BufferGeometryUtils = {
 
 			var newGeometry = geometry.clone();
 			newGeometry.setIndex( newIndices );
+			newGeometry.clearGroups();
 
 			return newGeometry;
 

examples/jsm/utils/BufferGeometryUtils.js

@@ -734,6 +734,7 @@ var BufferGeometryUtils = {
 
 			var newGeometry = geometry.clone();
 			newGeometry.setIndex( newIndices );
+			newGeometry.clearGroups();
 
 			return newGeometry;