function validate( opts, options ) {
	if ( !isObject( options ) ) {
		return new TypeError( format( 'invalid argument. Options argument must be an object. Value: `%s`.', options ) );
	}
	if ( hasOwnProp( options, 'thisArg' ) ) {
		opts.thisArg = options.thisArg;
	}
	return null;
}
Validates function options.

@private
@param {Object} opts - destination object
@param {Options} options - function options
@param {*} [options.thisArg] - execution context
@returns {(Error|null)} null or an error object

@example
var opts = {};
var options = {
    'thisArg': {}
};
var err = validate( opts, options );
if ( err ) {
    throw err;
}