bindings: Use an alias for @@iterator in certain declarations.

third_party/WebKit/Source/bindings/core/v8/Iterable.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef Iterable_h
 #define Iterable_h
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/V8IteratorResultValue.h"
 #include "bindings/core/v8/V8ScriptRunner.h"
@@ skipping 157 matching lines @@
       visitor->Trace(source_);
       Iterator::Trace(visitor);
     }
 
    private:
     Member<IterationSource> source_;
   };
 };
 
 // Utiltity mixin base-class for classes implementing IDL interfaces with
-// "iterable<T1, T2>".
+// "iterable<T1, T2>" or "maplike<T1, T2>".
 template <typename KeyType, typename ValueType>
 class PairIterable : public Iterable<KeyType, ValueType> {
  public:
   Iterator* GetIterator(ScriptState* script_state,
                         ExceptionState& exception_state) {
     return this->entriesForBinding(script_state, exception_state);
   }
 };
 
+// Utiltity mixin base-class for classes implementing IDL interfaces with
+// "setlike<V>" (not "iterable<V>").
+// IDL interfaces with "iterable<V>" (value iterators) inherit @@iterator,
+// values(), entries(), keys() and forEach() from the %ArrayPrototype%
+// intrinsic object automatically.
+template <typename ValueType>
+class SetlikeIterable : public Iterable<ValueType, ValueType> {
+ public:
+  Iterator* GetIterator(ScriptState* script_state,
+                        ExceptionState& exception_state) {
+    return this->valuesForBinding(script_state, exception_state);
+  }
+};
+
 }  // namespace blink
 
 #endif  // Iterable_h