[Isolates] Avoid dereferencing Isolate::Current() to check oddball identities...

src/objects-debug.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1220 matching lines @@
     info->number_of_slow_unused_properties_ +=
         dict->Capacity() - dict->NumberOfElements();
   }
   // Indexed properties
   switch (GetElementsKind()) {
     case FAST_ELEMENTS: {
       info->number_of_objects_with_fast_elements_++;
       int holes = 0;
       FixedArray* e = FixedArray::cast(elements());
       int len = e->length();
+      Heap* heap = HEAP;
       for (int i = 0; i < len; i++) {
-        if (e->get(i) == HEAP->the_hole_value()) holes++;
+        if (e->get(i) == heap->the_hole_value()) holes++;
       }
       info->number_of_fast_used_elements_   += len - holes;
       info->number_of_fast_unused_elements_ += holes;
       break;
     }
     case PIXEL_ELEMENTS: {
       info->number_of_objects_with_fast_elements_++;
       PixelArray* e = PixelArray::cast(elements());
       info->number_of_fast_used_elements_ += e->length();
       break;
@@ skipping 104 matching lines @@
       ASSERT(get(i)->IsTheHole());
       get(i)->Verify();
     }
   }
 }
 
 
 #endif  // DEBUG
 
 } }  // namespace v8::internal