client/signup/index.node.js
function setUpLocale( context, next ) {
	const language = getLanguage( context.params.lang );
	if ( language ) {
		context.lang = context.params.lang;
		if ( language.rtl ) {
			context.isRTL = true;
		}
	}

	next();
}
function setUpLocale( context, next ) {
	const language = getLanguage( context.params.lang );
	if ( language ) {
		context.lang = context.params.lang;
		if ( language.rtl ) {
			context.isRTL = true;
		}
	}

	next();
}
Set up the locale if there is one