remove most Isolate::Current asserts

src/mark-compact.cc

 // Copyright 2012 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 1390 matching lines @@
     collector->RecordSlot(anchor_slot, p, object);
     MarkBit mark = Marking::MarkBitFrom(object);
     collector->MarkObject(object, mark);
   }
 
 
   // Visit an unmarked object.
   INLINE(static void VisitUnmarkedObject(MarkCompactCollector* collector,
                                          HeapObject* obj)) {
 #ifdef DEBUG
-    ASSERT(Isolate::Current()->heap()->Contains(obj));
+    ASSERT(collector->heap()->Contains(obj));
     ASSERT(!HEAP->mark_compact_collector()->IsMarked(obj));
 #endif
     Map* map = obj->map();
     Heap* heap = obj->GetHeap();
     MarkBit mark = Marking::MarkBitFrom(obj);
     heap->mark_compact_collector()->SetMark(obj, mark);
     // Mark the map pointer and the body.
     MarkBit map_mark = Marking::MarkBitFrom(map);
     heap->mark_compact_collector()->MarkObject(map, map_mark);
     IterateBody(map, obj);
@@ skipping 2887 matching lines @@
   while (buffer != NULL) {
     SlotsBuffer* next_buffer = buffer->next();
     DeallocateBuffer(buffer);
     buffer = next_buffer;
   }
   *buffer_address = NULL;
 }
 
 
 } }  // namespace v8::internal