[heap] Avoid overzealous inclusion of heap internal headers.

src/heap/mark-compact.h

Index: src/heap/mark-compact.h
diff --git a/src/heap/mark-compact.h b/src/heap/mark-compact.h
index 9ae01fbe4ae22d1934a8090021354fb68a382374..502ffe5212835d1ee24a927bbf0453318ecdc615 100644
--- a/src/heap/mark-compact.h
+++ b/src/heap/mark-compact.h
@@ -28,7 +28,10 @@ class RootMarkingVisitor;
 
 class Marking : public AllStatic {
  public:
-  INLINE(static MarkBit MarkBitFrom(Address addr));
+  INLINE(static MarkBit MarkBitFrom(Address addr)) {
+    MemoryChunk* p = MemoryChunk::FromAddress(addr);
+    return p->markbits()->MarkBitFromIndex(p->AddressToMarkbitIndex(addr));
+  }
 
   INLINE(static MarkBit MarkBitFrom(HeapObject* obj)) {
     return MarkBitFrom(reinterpret_cast<Address>(obj));