Simple BlinkGC heap compaction.

third_party/WebKit/Source/platform/heap/MarkingVisitorImpl.h

Index: third_party/WebKit/Source/platform/heap/MarkingVisitorImpl.h
diff --git a/third_party/WebKit/Source/platform/heap/MarkingVisitorImpl.h b/third_party/WebKit/Source/platform/heap/MarkingVisitorImpl.h
index 5d63592e92ef1e2454323576fc57533e3e97831d..22c5cbd0900f82fb1bd0f71293c41dabc645cde5 100644
--- a/third_party/WebKit/Source/platform/heap/MarkingVisitorImpl.h
+++ b/third_party/WebKit/Source/platform/heap/MarkingVisitorImpl.h
@@ -88,6 +88,21 @@ class MarkingVisitorImpl {
   }
 #endif
 
+  inline void registerMovingObjectReference(MovableReference* slot) {
+    if (toDerived()->getMarkingMode() != Visitor::GlobalMarkingWithCompaction)
+      return;
+    toDerived()->heap().registerMovingObjectReference(slot);
+  }
+
+  inline void registerMovingObjectCallback(MovableReference reference,
+                                           MovingObjectCallback callback,
+                                           void* callbackData) {
+    if (toDerived()->getMarkingMode() != Visitor::GlobalMarkingWithCompaction)
+      return;
+    toDerived()->heap().registerMovingObjectCallback(reference, callback,
+                                                     callbackData);
+  }
+
   inline bool ensureMarked(const void* objectPointer) {
     if (!objectPointer)
       return false;