bindings: Add validation for enum Sequence or Array

Source/bindings/core/v8/V8Binding.h

Index: Source/bindings/core/v8/V8Binding.h
diff --git a/Source/bindings/core/v8/V8Binding.h b/Source/bindings/core/v8/V8Binding.h
index bd91db5a69109c53e1531e03ef5305a37f005f95..dd1acf04c2aa80cec3b403473e936c19390720dd 100644
--- a/Source/bindings/core/v8/V8Binding.h
+++ b/Source/bindings/core/v8/V8Binding.h
@@ -323,6 +323,9 @@ inline String toCoreString(v8::Handle<v8::String> value)
     return v8StringToWebCoreString<String>(value, Externalize);
 }
 
+// Convert a V8 value to a WTF::String.
+String toCoreString(v8::Isolate*, v8::Local<v8::Value>);
+
 inline String toCoreStringWithNullCheck(v8::Handle<v8::String> value)
 {
     if (value.IsEmpty() || value->IsNull())
@@ -919,6 +922,9 @@ template<class Collection> static void indexedPropertyEnumerator(const v8::Prope
     v8SetReturnValue(info, properties);
 }
 
+bool isValidEnum(const String value, const char** validValues, size_t length);
+bool isValidEnum(const Vector<String>& values, const char** validValues, size_t length);
+
 // These methods store hidden values into an array that is stored in the internal field of a DOM wrapper.
 void addHiddenValueToArray(v8::Isolate*, v8::Handle<v8::Object>, v8::Local<v8::Value>, int cacheIndex);
 void removeHiddenValueFromArray(v8::Isolate*, v8::Handle<v8::Object>, v8::Local<v8::Value>, int cacheIndex);