Update context: getPageTitle

[kitajchuk]

getPageTitle () {
        const page = this.get( "page" );;
        const site = this.get( "site" );
        const navi = this.get( "navi" );
        const items = this.get( "items" );
        let item = this.get( "item" );
        let title = site.data.title;
        let navItem = null;

        if ( typeof title === "object" ) {
            title = prismicDOM.RichText.asText( title );
        }

        // Supports collection mapping to content-type
        if ( items ) {
            item = navi.items.find(( nav ) => {
                return (nav.uid === page);
            });

            if ( item ) {
                item.data = {
                    title: item.title
                };
            }

        } else if ( item && (typeof item.data.title === "object") ) {
            item.data.title = prismicDOM.RichText.asText( item.data.title );
        }

        title = (item ? `${item.data.title} — ${title}` : title);

        return title;
    }