Source

File: wp-includes/class.wp-scripts.php

public function print_extra_script( $handle, $echo = true ) {
		$output = $this->get_data( $handle, 'data' );
		if ( ! $output ) {
			return;
		}

		if ( ! $echo ) {
			return $output;
		}

		printf( "<script%s id='%s-js-extra'>\n", $this->type_attr, esc_attr( $handle ) );

		// CDATA is not needed for HTML 5.
		if ( $this->type_attr ) {
			echo "/* <![CDATA[ */\n";
		}

		echo "$output\n";

		if ( $this->type_attr ) {
			echo "/* ]]> */\n";
		}

		echo "</script>\n";

		return true;
	}