ES6 symbols: Implement Symbol intrinsic and basic functionality

src/v8globals.h

Index: src/v8globals.h
diff --git a/src/v8globals.h b/src/v8globals.h
index 70a7e915c193e2448de07de0aa11c857c1a38590..b86aa39952acd6e3f4327c7e1d1ec7b11d3e4381 100644
--- a/src/v8globals.h
+++ b/src/v8globals.h
@@ -273,6 +273,7 @@ enum InlineCacheState {
 enum CheckType {
   RECEIVER_MAP_CHECK,
   STRING_CHECK,
+  SYMBOL_CHECK,
   NUMBER_CHECK,
   BOOLEAN_CHECK
 };
@@ -290,7 +291,7 @@ enum CallFunctionFlags {
 
 enum InlineCacheHolderFlag {
   OWN_MAP,  // For fast properties objects.
-  PROTOTYPE_MAP  // For slow properties objects (except GlobalObjects).
+  DELEGATE_MAP  // For slow properties objects (except GlobalObjects).
 };