[bindings] Let NativeValueTraits<T>::nativeValue be variadic function and merge various convers…

Source/bindings/modules/v8/V8BindingForModulesTest.cpp

Index: Source/bindings/modules/v8/V8BindingForModulesTest.cpp
diff --git a/Source/bindings/modules/v8/V8BindingForModulesTest.cpp b/Source/bindings/modules/v8/V8BindingForModulesTest.cpp
index cece895d69b0846b9d6ebc9f00983afaba76964e..578a326e71ff8c9a6f15bda47d78d22412010453 100644
--- a/Source/bindings/modules/v8/V8BindingForModulesTest.cpp
+++ b/Source/bindings/modules/v8/V8BindingForModulesTest.cpp
@@ -42,8 +42,8 @@ IDBKey* checkKeyFromValueAndKeyPathInternal(v8::Isolate* isolate, const ScriptVa
 {
     IDBKeyPath idbKeyPath(keyPath);
     EXPECT_TRUE(idbKeyPath.isValid());
-
-    return createIDBKeyFromScriptValueAndKeyPath(isolate, value, idbKeyPath);
+    NonThrowableExceptionState exceptionState;

[bashi, 2015/03/19 23:53:41]

Can we pass exceptionState from the caller of this function? We want to minimize
use of NonThrowableExceptionState. If it's difficult, please add a TODO comment.

I understand some nativeValue() methods never throw an exception via
exceptionState, but it could be changed in the future and if that happens we
will swallow exceptions unexpectedly.

+    return ScriptValue::to<IDBKey*>(isolate, value, exceptionState, idbKeyPath);
 }
 
 void checkKeyPathNullValue(v8::Isolate* isolate, const ScriptValue& value, const String& keyPath)