Change and disable global handle zapping.

R=yangguo@chromium.org
BUG=chromium:176056
TEST=webkit:storage/indexeddb/create-and-remove-object-store.html

Review URL: https://codereview.chromium.org/12300009

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13680 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/global-handles.cc

@@ -76,7 +76,7 @@ class GlobalHandles::Node {
   ~Node() {
     // TODO(1428): if it's a weak handle we should have invoked its callback.
     // Zap the values for eager trapping.
-    object_ = NULL;
+    object_ = reinterpret_cast<Object*>(kGlobalHandleZapValue);
     class_id_ = v8::HeapProfiler::kPersistentHandleNoClassId;
     index_ = 0;
     set_independent(false);
@@ -113,9 +113,10 @@ class GlobalHandles::Node {
   void Release(GlobalHandles* global_handles) {
     ASSERT(state() != FREE);
     set_state(FREE);
-#ifdef DEBUG
+    // TODO(176056): Enable as soon as WebKit bindings are fixed.
+#ifdef DEBUG_TODO
     // Zap the values for eager trapping.
-    object_ = NULL;
+    object_ = reinterpret_cast<Object*>(kGlobalHandleZapValue);
     class_id_ = v8::HeapProfiler::kPersistentHandleNoClassId;
     set_independent(false);
     set_partially_dependent(false);

src/v8globals.h

@@ -71,6 +71,8 @@ const Address kZapValue =
     reinterpret_cast<Address>(V8_UINT64_C(0xdeadbeedbeadbeef));
 const Address kHandleZapValue =
     reinterpret_cast<Address>(V8_UINT64_C(0x1baddead0baddeaf));
+const Address kGlobalHandleZapValue =
+    reinterpret_cast<Address>(V8_UINT64_C(0x1baffed00baffedf));
 const Address kFromSpaceZapValue =
     reinterpret_cast<Address>(V8_UINT64_C(0x1beefdad0beefdaf));
 const uint64_t kDebugZapValue = V8_UINT64_C(0xbadbaddbbadbaddb);
@@ -79,6 +81,7 @@ const uint64_t kFreeListZapValue = 0xfeed1eaffeed1eaf;
 #else
 const Address kZapValue = reinterpret_cast<Address>(0xdeadbeef);
 const Address kHandleZapValue = reinterpret_cast<Address>(0xbaddeaf);
+const Address kGlobalHandleZapValue = reinterpret_cast<Address>(0xbaffedf);
 const Address kFromSpaceZapValue = reinterpret_cast<Address>(0xbeefdaf);
 const uint32_t kSlotsZapValue = 0xbeefdeef;
 const uint32_t kDebugZapValue = 0xbadbaddb;