[Reland] Correct fixed-position recording for Slimming Paint

Source/platform/graphics/paint/DisplayItem.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef DisplayItem_h
 #define DisplayItem_h
 
 #include "platform/PlatformExport.h"
 #include "platform/graphics/paint/DisplayItemClient.h"
 #include "wtf/Assertions.h"
@@ skipping 130 matching lines @@
         EndTransform3DLast = EndTransform3DFirst + Transform3DLast - Transform3DFirst,
 
         BeginFilter,
         EndFilter,
         BeginCompositing,
         EndCompositing,
         BeginTransform,
         EndTransform,
         BeginClipPath,
         EndClipPath,
+        BeginFixedPosition,
+        EndFixedPosition,
+        BeginFixedPositionContainer,
+        EndFixedPositionContainer,
 
         SubtreeCachedFirst,
         SubtreeCachedPaintPhaseFirst = SubtreeCachedFirst,
         SubtreeCachedPaintPhaseLast = SubtreeCachedPaintPhaseFirst + PaintPhaseMax,
         SubtreeCachedLast = SubtreeCachedPaintPhaseLast,
 
         BeginSubtreeFirst,
         BeginSubtreePaintPhaseFirst = BeginSubtreeFirst,
         BeginSubtreePaintPhaseLast = BeginSubtreePaintPhaseFirst + PaintPhaseMax,
         BeginSubtreeLast = BeginSubtreePaintPhaseLast,
@@ skipping 146 matching lines @@
     virtual bool isEndAndPairedWith(const DisplayItem& other) const override = 0;
 #endif
 
 private:
     virtual bool isEnd() const override final { return true; }
 };
 
 } // namespace blink
 
 #endif // DisplayItem_h