Make messageFormatterFn backwards compatible

The new version adds a string "call" parameter
after the formatter function.
Old bundles will not have this parameter, so messageFormatterFn
will use the old behavior.

Author: nkovacs

src/message.js

@@ -115,14 +115,15 @@ Globalize.prototype.messageFormatter = function( path ) {
 	);
 
 	returnFn = messageFormatterFn.apply( this, [
-		formatter,
+		formatter, "call",
 		runtime.number, runtime.plural, runtime.select, pluralGenerator
 	].concat( compiler.formatters ) );
 
 	var runtimeArgs = [
 		messageFormatterRuntimeBind(
 			formatter, formatterSrc, compiler.runtime, pluralType, cldr.locale, compiler.formatters
-		)
+		),
+		"call"
 	];
 
 	if ( pluralGenerator ) {

src/message/formatter-fn.js

@@ -2,8 +2,10 @@ define([
 	"../common/validate/parameter-type/message-variables"
 ], function( validateParameterTypeMessageVariables ) {
 
-return function( formatter ) {
-	formatter = formatter.apply( null, [].slice.call( arguments, 1 ) );
+return function( formatter, shouldCall ) {
+	if ( shouldCall === "call" ) {
+		formatter = formatter.apply( null, [].slice.call( arguments, 2 ) );
+	}
 	return function messageFormatter( variables ) {
 		if ( typeof variables === "number" || typeof variables === "string" ) {
 			variables = [].slice.call( arguments, 0 );