Unify symbols sharing across native scripts and runtime.

src/collection.js

Index: src/collection.js
diff --git a/src/collection.js b/src/collection.js
index 6d43384e1cecf440de2abc3067cab0a51528ae9c..3d1e9573f24467553ec00df6a717ba1c71a389ea 100644
--- a/src/collection.js
+++ b/src/collection.js
@@ -16,6 +16,7 @@ var $getExistingHash;
 var GlobalMap = global.Map;
 var GlobalObject = global.Object;
 var GlobalSet = global.Set;
+var HashCodeSymbol = utils.GetPrivateSymbol("hash_code_symbol");
 var IntRandom;
 
 utils.Import(function(from) {
@@ -90,8 +91,6 @@ function ComputeIntegerHash(key, seed) {
 }
 %SetForceInlineFlag(ComputeIntegerHash);
 
-var hashCodeSymbol = GLOBAL_PRIVATE("hash_code_symbol");
-
 function GetExistingHash(key) {
   if (%_IsSmi(key)) {
     return ComputeIntegerHash(key, 0);
@@ -102,7 +101,7 @@ function GetExistingHash(key) {
       return field >>> 2 /* Name::kHashShift */;
     }
   } else if (IS_SPEC_OBJECT(key) && !%_IsJSProxy(key) && !IS_GLOBAL(key)) {
-    var hash = GET_PRIVATE(key, hashCodeSymbol);
+    var hash = GET_PRIVATE(key, HashCodeSymbol);
     return hash;
   }
   return %GenericHash(key);
@@ -115,7 +114,7 @@ function GetHash(key) {
   if (IS_UNDEFINED(hash)) {
     hash = IntRandom() | 0;
     if (hash === 0) hash = 1;
-    SET_PRIVATE(key, hashCodeSymbol, hash);
+    SET_PRIVATE(key, HashCodeSymbol, hash);
   }
   return hash;
 }