[heap] New Dijkstra marking write barrier.

src/heap/spaces.h

Index: src/heap/spaces.h
diff --git a/src/heap/spaces.h b/src/heap/spaces.h
index 94ab4dc513e1bb296ccd7d5bb05daa8b661345b7..40604d424cc425b43871446b53d41599fd395a6c 100644
--- a/src/heap/spaces.h
+++ b/src/heap/spaces.h
@@ -631,13 +631,6 @@ class MemoryChunk {
     }
   }
 
-  bool IsLeftOfProgressBar(Object** slot) {
-    Address slot_address = reinterpret_cast<Address>(slot);
-    DCHECK(slot_address > this->address());
-    return (slot_address - (this->address() + kObjectStartOffset)) <
-           progress_bar();
-  }
-
   size_t size() const { return size_; }
 
   void set_size(size_t size) { size_ = size; }