Don't throw target.apply is not a function

For #705

lib/extension.js

@@ -215,7 +215,7 @@
 					return original.apply(thisArg, args);
 				}
 				catch (error){
-					return target.apply(thisArg, args);
+					return scope.getWrapped(target).apply(thisArg, args);
 				}
 			}
 		}, window, "");