- Revert r24564 and r24563 due to unexplained malloc corruption.

runtime/lib/object_patch.dart

Index: runtime/lib/object_patch.dart
===================================================================
--- runtime/lib/object_patch.dart	(revision 24564)
+++ runtime/lib/object_patch.dart	(working copy)
@@ -4,26 +4,20 @@
 
 patch class Object {
 
-  // Helpers used to implement hashCode. If a hashCode is used, we remember it
-  // in a weak table in the VM. A new hashCode value is calculated using a
+  // Helpers used to implement hashCode. If a hashCode is used we remember it
+  // using an Expando object. A new hashCode value is calculated using a Random
   // number generator.
-  static final _hashCodeRnd = new Random();
+  static Expando _hashCodeExp = new Expando("Object.hashCode");
+  static Random _hashCodeRnd = new Random();
 
-  static _getHash(obj) native "Object_getHash";
-  static _setHash(obj, hash) native "Object_setHash";
-
   /* patch */ int get hashCode {
     if (this == null) {
       return 2011;  // The year Dart was announced and a prime.
     }
-    var result = _getHash(this);
-    if (result == 0) {
-      // We want the hash to be a Smi value greater than 0.
-      result = _hashCodeRnd.nextInt(0x40000000);
-      while (result == 0) {
-        result = _hashCodeRnd.nextInt(0x40000000);
-      }
-      _setHash(this, result);
+    var result = _hashCodeExp[this];
+    if (result == null) {
+      result = _hashCodeRnd.nextInt(0x40000000);  // Stay in Smi range.
+      _hashCodeExp[this] = result;
     }
     return result;
   }