Examples: Clean up

examples/webgl_buffergeometry_instancing_dynamic.html

@@ -130,7 +130,6 @@
 			var geometry = new THREE.InstancedBufferGeometry();
 			geometry.index = bufferGeometry.index;
 			geometry.attributes = bufferGeometry.attributes;
-			geometry.groups = bufferGeometry.groups;
 
 			// per instance data