String.prototype[Symbol.iterator] does RequireObjectCoercible(this)

BUG=v8:4348
R=adamk
LOG=Y

Review URL: https://codereview.chromium.org/1783643002

Cr-Commit-Position: refs/heads/master@{#34647}

src/js/string-iterator.js

@@ -32,6 +32,7 @@ function StringIterator() {}
 
 // 21.1.5.1 CreateStringIterator Abstract Operation
 function CreateStringIterator(string) {
+  CHECK_OBJECT_COERCIBLE(string, 'String.prototype[Symbol.iterator]');
   var s = TO_STRING(string);
   var iterator = new StringIterator;
   SET_PRIVATE(iterator, stringIteratorIteratedStringSymbol, s);

test/test262/test262.status

@@ -50,9 +50,6 @@
   # https://code.google.com/p/v8/issues/detail?id=4163
   'built-ins/GeneratorPrototype/next/context-constructor-invocation': [FAIL],
 
-  # https://code.google.com/p/v8/issues/detail?id=4348
-  'built-ins/String/prototype/Symbol.iterator/this-val-non-obj-coercible': [FAIL],
-
   # The order of adding the name property is wrong
   # https://code.google.com/p/v8/issues/detail?id=4199
   'language/computed-property-names/class/static/method-number': [FAIL, FAIL_SLOPPY],