Revert of [heap] Remove black pages and use black areas instead.

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 01170333d7bc6b421e4a294d7d278b5a72cbaa74..6a238839b18eb55d6139f1d83cc159a85343532c 100644
--- a/src/heap/mark-compact.h
+++ b/src/heap/mark-compact.h
@@ -218,19 +218,7 @@
 
   inline void Advance() {
     cell_index_++;
-    cell_base_ += Bitmap::kBitsPerCell * kPointerSize;
-  }
-
-  inline bool Advance(unsigned int new_cell_index) {
-    if (new_cell_index != cell_index_) {
-      DCHECK_GT(new_cell_index, cell_index_);
-      DCHECK_LE(new_cell_index, last_cell_index_);
-      unsigned int diff = new_cell_index - cell_index_;
-      cell_index_ = new_cell_index;
-      cell_base_ += diff * (Bitmap::kBitsPerCell * kPointerSize);
-      return true;
-    }
-    return false;
+    cell_base_ += 32 * kPointerSize;
   }
 
   // Return the next mark bit cell. If there is no next it returns 0;
@@ -265,6 +253,8 @@
         it_(chunk_),
         cell_base_(it_.CurrentCellBase()),
         current_cell_(*it_.CurrentCell()) {
+    // Black pages can not be iterated.
+    DCHECK(!chunk->IsFlagSet(Page::BLACK_PAGE));
   }
 
   HeapObject* Next();