Make classes and structures in core/dom fast-allocated.

Source/core/dom/Fullscreen.h

Index: Source/core/dom/Fullscreen.h
diff --git a/Source/core/dom/Fullscreen.h b/Source/core/dom/Fullscreen.h
index 24ff00033d5df5357335645d76b2743136c280cc..8e8a8639599dcab5fb172f6a40c6c99a23332d2b 100644
--- a/Source/core/dom/Fullscreen.h
+++ b/Source/core/dom/Fullscreen.h
@@ -48,6 +48,7 @@ class CORE_EXPORT Fullscreen final
     : public NoBaseWillBeGarbageCollectedFinalized<Fullscreen>
     , public WillBeHeapSupplement<Document>
     , public DocumentLifecycleObserver {
+    WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED(Fullscreen);
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(Fullscreen);
 public:
     virtual ~Fullscreen();