[bindings] Introduce ScriptValue.to<T> to convert to native values.

Source/modules/indexeddb/IDBFactory.cpp

Index: Source/modules/indexeddb/IDBFactory.cpp
diff --git a/Source/modules/indexeddb/IDBFactory.cpp b/Source/modules/indexeddb/IDBFactory.cpp
index c129db91df9e1e716080f42fdda7e430193cc633..63c21186f5a84a66a982976defa314d77cd0a193 100644
--- a/Source/modules/indexeddb/IDBFactory.cpp
+++ b/Source/modules/indexeddb/IDBFactory.cpp
@@ -155,8 +155,8 @@ IDBOpenDBRequest* IDBFactory::deleteDatabase(ScriptState* scriptState, const Str
 
 short IDBFactory::cmp(ScriptState* scriptState, const ScriptValue& firstValue, const ScriptValue& secondValue, ExceptionState& exceptionState)
 {
-    IDBKey* first = scriptValueToIDBKey(scriptState->isolate(), firstValue);
-    IDBKey* second = scriptValueToIDBKey(scriptState->isolate(), secondValue);
+    IDBKey* first = firstValue.to<IDBKey*>(exceptionState);
+    IDBKey* second = secondValue.to<IDBKey*>(exceptionState);
 
     ASSERT(first);
     ASSERT(second);