Keep a persistent handle for the bindings classes to avoid repeated lookups that involve performing…

Source/bindings/dart/DartDOMData.h

Index: Source/bindings/dart/DartDOMData.h
diff --git a/Source/bindings/dart/DartDOMData.h b/Source/bindings/dart/DartDOMData.h
index 2f6927dc0214e394716dc9653ce0ef7533463b45..db093775cead55d23436e851c37039fa547b7fbe 100644
--- a/Source/bindings/dart/DartDOMData.h
+++ b/Source/bindings/dart/DartDOMData.h
@@ -31,6 +31,7 @@
 #ifndef DartDOMData_h
 #define DartDOMData_h
 
+#include "DartWebkitClassIds.h"
 #include "bindings/dart/DartStringCache.h"
 
 #include "wtf/HashMap.h"
@@ -64,6 +65,7 @@ typedef HashMap<EventTarget*, Dart_WeakPersistentHandle> DartEventTargetMap;
 typedef HashSet<DartWeakCallback*> DartWeakCallbacks;
 typedef HashSet<DartIsolateDestructionObserver*> DartIsolateDestructionObservers;
 typedef HashMap<String, Dart_PersistentHandle> DartCustomElementMap;
+typedef Dart_PersistentHandle ClassTable[NumWebkitClassIds];
 
 class DartDOMData {
 public:
@@ -97,6 +99,7 @@ public:
     DartIsolateDestructionObservers* isolateDestructionObservers() { return &m_isolateDestructionObservers; }
     DartCustomElementMap* customElementMap() { return &m_customElementMap; }
     DartCustomElementMap* customBaseElementMap() { return &m_customBaseElementMap; }
+    ClassTable* classHandleCache() { return &m_classHandleCache; }
 
 private:
     ScriptExecutionContext* m_scriptExecutionContext;
@@ -118,6 +121,7 @@ private:
     DartIsolateDestructionObservers m_isolateDestructionObservers;
     DartCustomElementMap m_customElementMap;
     DartCustomElementMap m_customBaseElementMap;
+    ClassTable m_classHandleCache;
 };
 
 }