support for arrow funcion expressions as caller/sanitizers (fixes #7)

* check that expression.callee.property exists
* when defining funcName, check that either one of its possible values exist first. left out that it was an OR condition. also check that funcName is valid afterwards

lib/rules/no-unsafe-innerhtml.js

@@ -70,9 +70,9 @@ module.exports = function (context) {
             } else {
                 allowed = false;
             }
-        } else if (expression.type === "CallExpression") {
+        } else if ((expression.type === "CallExpression") && (expression.callee.property || expression.callee.name)) {
             var funcName = expression.callee.name || expression.callee.property.name;
-            if (VALID_UNWRAPPERS.indexOf(funcName) !== -1) {
+            if ( funcName && VALID_UNWRAPPERS.indexOf(funcName) !== -1) {
                 allowed = true;
             }
         } else if (expression.type === "BinaryExpression") {