Fix false positive in es-x/no-nonstandard-iterator-prototype-properties rule (#230)

Author: ota-meshi

lib/util/well-known-properties.js

@@ -851,6 +851,18 @@ const iteratorProperties = new Set([
 const iteratorPrototypeProperties = new Set([
     ...objectPrototypeProperties,
 
+    // https://tc39.es/ecma262/multipage/control-abstraction-objects.html#table-iterator-interface-required-properties
+    "next",
+
+    // https://tc39.es/ecma262/multipage/control-abstraction-objects.html#table-iterator-interface-optional-properties
+    "return",
+    "throw",
+
+    // https://tc39.es/ecma262/multipage/control-abstraction-objects.html#sec-%iteratorhelperprototype%-object
+    "next",
+    "return",
+    // [ %Symbol.toStringTag% ]
+
     // https://tc39.es/ecma262/multipage/control-abstraction-objects.html#sec-%iterator.prototype%-object
     "constructor",
     "drop",

tests/lib/rules/no-nonstandard-iterator-prototype-properties.js

@@ -13,6 +13,9 @@ new RuleTester().run(ruleId, rule, {
         "foo",
         "foo.toString",
         "foo.foo",
+        "[].keys().next()",
+        "[].keys().return()",
+        "[].keys().throw()",
         ...[...iteratorPrototypeProperties].map(
             (p) => `Iterator.from({}).${p}`,
         ),