Increment property tree sequence number when updating.

third_party/WebKit/Source/platform/graphics/compositing/PropertyTreeManager.h

 // Copyright 2015 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 PropertyTreeManager_h
 #define PropertyTreeManager_h
 
 #include "wtf/HashMap.h"
 #include "wtf/HashSet.h"
 #include "wtf/Noncopyable.h"
@@ skipping 14 matching lines @@
 class EffectPaintPropertyNode;
 class ScrollPaintPropertyNode;
 class TransformPaintPropertyNode;
 
 // Mutates a cc property tree to reflect Blink paint property tree
 // state. Intended for use by PaintArtifactCompositor.
 class PropertyTreeManager {
   WTF_MAKE_NONCOPYABLE(PropertyTreeManager);
 
  public:
-  PropertyTreeManager(cc::PropertyTrees&, cc::Layer* rootLayer);
-
-  static constexpr int kPropertyTreeSequenceNumber = 1;
+  PropertyTreeManager(cc::PropertyTrees&,
+                      cc::Layer* rootLayer,
+                      int sequenceNumber);
 
   void setupRootTransformNode();
   void setupRootClipNode();
   void setupRootEffectNode();
   void setupRootScrollNode();
 
   // A brief discourse on cc property tree nodes, identifiers, and current and
   // future design evolution envisioned:
   //
   // cc property trees identify nodes by their |id|, which implementation-wise
@@ skipping 63 matching lines @@
   HashMap<const ClipPaintPropertyNode*, int> m_clipNodeMap;
   HashMap<const ScrollPaintPropertyNode*, int> m_scrollNodeMap;
 
   struct BlinkEffectAndCcIdPair {
     const EffectPaintPropertyNode* effect;
     // The cc property tree effect node id, or 'node index', for the cc effect
     // node corresponding to the above Blink effect paint property node.
     int id;
   };
   Vector<BlinkEffectAndCcIdPair> m_effectStack;
+  int m_sequenceNumber;
 
 #if DCHECK_IS_ON()
   HashSet<const EffectPaintPropertyNode*> m_effectNodesConverted;
 #endif
 };
 
 }  // namespace blink
 
 #endif  // PropertyTreeManager_h