Revert r8619 because of Webkit failures.

src/api.cc

Index: src/api.cc
===================================================================
--- src/api.cc	(revision 8625)
+++ src/api.cc	(working copy)
@@ -3085,7 +3085,39 @@
   ENTER_V8(isolate);
   i::HandleScope scope(isolate);
   i::Handle<i::JSObject> self = Utils::OpenHandle(this);
-  return i::GetIdentityHash(self)->value();
+  i::Handle<i::Object> hidden_props_obj(i::GetHiddenProperties(self, true));
+  if (!hidden_props_obj->IsJSObject()) {
+    // We failed to create hidden properties.  That's a detached
+    // global proxy.
+    ASSERT(hidden_props_obj->IsUndefined());
+    return 0;
+  }
+  i::Handle<i::JSObject> hidden_props =
+      i::Handle<i::JSObject>::cast(hidden_props_obj);
+  i::Handle<i::String> hash_symbol = isolate->factory()->identity_hash_symbol();
+  if (hidden_props->HasLocalProperty(*hash_symbol)) {
+    i::Handle<i::Object> hash = i::GetProperty(hidden_props, hash_symbol);
+    CHECK(!hash.is_null());
+    CHECK(hash->IsSmi());
+    return i::Smi::cast(*hash)->value();
+  }
+
+  int hash_value;
+  int attempts = 0;
+  do {
+    // Generate a random 32-bit hash value but limit range to fit
+    // within a smi.
+    hash_value = i::V8::Random(self->GetIsolate()) & i::Smi::kMaxValue;
+    attempts++;
+  } while (hash_value == 0 && attempts < 30);
+  hash_value = hash_value != 0 ? hash_value : 1;  // never return 0
+  CHECK(!i::SetLocalPropertyIgnoreAttributes(
+          hidden_props,
+          hash_symbol,
+          i::Handle<i::Object>(i::Smi::FromInt(hash_value)),
+          static_cast<PropertyAttributes>(None)).is_null());
+
+  return hash_value;
 }