Revert of [heap] Avoid the use of cells to point from code to new-space objects.

src/heap/remembered-set.h

Index: src/heap/remembered-set.h
diff --git a/src/heap/remembered-set.h b/src/heap/remembered-set.h
index ab5badf5cd05e811d8a34a3f8347cdd0b41ccbe9..339748cbd723e5aedd36906e721924e98e54244c 100644
--- a/src/heap/remembered-set.h
+++ b/src/heap/remembered-set.h
@@ -345,20 +345,6 @@
   }
 };
 
-inline SlotType SlotTypeForRelocInfoMode(RelocInfo::Mode rmode) {
-  if (RelocInfo::IsCodeTarget(rmode)) {
-    return CODE_TARGET_SLOT;
-  } else if (RelocInfo::IsCell(rmode)) {
-    return CELL_TARGET_SLOT;
-  } else if (RelocInfo::IsEmbeddedObject(rmode)) {
-    return EMBEDDED_OBJECT_SLOT;
-  } else if (RelocInfo::IsDebugBreakSlot(rmode)) {
-    return DEBUG_TARGET_SLOT;
-  }
-  UNREACHABLE();
-  return NUMBER_OF_SLOT_TYPES;
-}
-
 }  // namespace internal
 }  // namespace v8