Material: Documented onBeforeCompile expected parameters.

src/materials/Material.js

@@ -83,7 +83,7 @@ Material.prototype = Object.assign( Object.create( EventDispatcher.prototype ),
 
 	isMaterial: true,
 
-	onBeforeCompile: function () {},
+	onBeforeCompile: function ( /* shaderobject, renderer */ ) {},
 
 	setValues: function ( values ) {