Set layer scroll data from PaintArtifactCompositor

third_party/WebKit/Source/platform/graphics/paint/ScrollPaintPropertyNode.h

 // Copyright 2016 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 ScrollPaintPropertyNode_h
 #define ScrollPaintPropertyNode_h
 
 #include "platform/PlatformExport.h"
 #include "platform/geometry/FloatSize.h"
 #include "platform/scroll/MainThreadScrollingReason.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/RefPtr.h"
 #include "wtf/text/WTFString.h"
 
 #include <iosfwd>
 
 namespace blink {
 
 using MainThreadScrollingReasons = uint32_t;
+class WebLayerScrollClient;
 
 // A scroll node contains auxiliary scrolling information which includes how far
 // an area can be scrolled, main thread scrolling reasons, etc. Scroll nodes
 // are owned by TransformPaintPropertyNodes that are used for the scroll offset
 // translation.
 //
 // Main thread scrolling reasons force scroll updates to go to the main thread
 // and can have dependencies on other nodes. For example, all parents of a
 // scroll node with background attachment fixed set should also have it set.
 //
 // The scroll tree differs from the other trees because it does not affect
 // geometry directly. We may want to rename this class to reflect that it is
 // more like rare scroll data for TransformPaintPropertyNode.
 class PLATFORM_EXPORT ScrollPaintPropertyNode
     : public RefCounted<ScrollPaintPropertyNode> {
  public:
   // This node is really a sentinel, and does not represent a real scroll.
   static ScrollPaintPropertyNode* root();
 
   static PassRefPtr<ScrollPaintPropertyNode> create(
       PassRefPtr<const ScrollPaintPropertyNode> parent,
       const IntSize& clip,
       const IntSize& bounds,
       bool userScrollableHorizontal,
       bool userScrollableVertical,
-      MainThreadScrollingReasons mainThreadScrollingReasons) {
+      MainThreadScrollingReasons mainThreadScrollingReasons,
+      WebLayerScrollClient* scrollClient) {
     return adoptRef(new ScrollPaintPropertyNode(
         std::move(parent), clip, bounds, userScrollableHorizontal,
-        userScrollableVertical, mainThreadScrollingReasons));
+        userScrollableVertical, mainThreadScrollingReasons, scrollClient));
   }
 
   void update(PassRefPtr<const ScrollPaintPropertyNode> parent,
               const IntSize& clip,
               const IntSize& bounds,
               bool userScrollableHorizontal,
               bool userScrollableVertical,
-              MainThreadScrollingReasons mainThreadScrollingReasons) {
+              MainThreadScrollingReasons mainThreadScrollingReasons,
+              WebLayerScrollClient* scrollClient) {
     DCHECK(!isRoot());
     DCHECK(parent != this);
     m_parent = parent;
     m_clip = clip;
     m_bounds = bounds;
     m_userScrollableHorizontal = userScrollableHorizontal;
     m_userScrollableVertical = userScrollableVertical;
     m_mainThreadScrollingReasons = mainThreadScrollingReasons;
+    m_scrollClient = scrollClient;
   }
 
   const ScrollPaintPropertyNode* parent() const { return m_parent.get(); }
   bool isRoot() const { return !m_parent; }
 
   // The clipped area that contains the scrolled content.
   const IntSize& clip() const { return m_clip; }
 
   // The bounds of the content that is scrolled within |clip|.
   const IntSize& bounds() const { return m_bounds; }
@@ skipping 11 matching lines @@
     return m_mainThreadScrollingReasons &
            MainThreadScrollingReason::kThreadedScrollingDisabled;
   }
 
   // Main thread scrolling reason for background attachment fixed descendants.
   bool hasBackgroundAttachmentFixedDescendants() const {
     return m_mainThreadScrollingReasons &
            MainThreadScrollingReason::kHasBackgroundAttachmentFixedObjects;
   }
 
+  WebLayerScrollClient* scrollClient() const { return m_scrollClient; }
+
 #if DCHECK_IS_ON()
   // The clone function is used by FindPropertiesNeedingUpdate.h for recording
   // a scroll node before it has been updated, to later detect changes.
   PassRefPtr<ScrollPaintPropertyNode> clone() const {
     RefPtr<ScrollPaintPropertyNode> cloned =
         adoptRef(new ScrollPaintPropertyNode(
             m_parent, m_clip, m_bounds, m_userScrollableHorizontal,
-            m_userScrollableVertical, m_mainThreadScrollingReasons));
+            m_userScrollableVertical, m_mainThreadScrollingReasons,
+            m_scrollClient));
     return cloned;
   }
 
   // The equality operator is used by FindPropertiesNeedingUpdate.h for checking
   // if a scroll node has changed.
   bool operator==(const ScrollPaintPropertyNode& o) const {
     return m_parent == o.m_parent && m_clip == o.m_clip &&
            m_bounds == o.m_bounds &&
            m_userScrollableHorizontal == o.m_userScrollableHorizontal &&
            m_userScrollableVertical == o.m_userScrollableVertical &&
-           m_mainThreadScrollingReasons == o.m_mainThreadScrollingReasons;
+           m_mainThreadScrollingReasons == o.m_mainThreadScrollingReasons &&
+           m_scrollClient == o.m_scrollClient;
   }
 
   String toTreeString() const;
 #endif
 
   String toString() const;
 
  private:
   ScrollPaintPropertyNode(PassRefPtr<const ScrollPaintPropertyNode> parent,
                           IntSize clip,
                           IntSize bounds,
                           bool userScrollableHorizontal,
                           bool userScrollableVertical,
-                          MainThreadScrollingReasons mainThreadScrollingReasons)
+                          MainThreadScrollingReasons mainThreadScrollingReasons,
+                          WebLayerScrollClient* scrollClient)
       : m_parent(parent),
         m_clip(clip),
         m_bounds(bounds),
         m_userScrollableHorizontal(userScrollableHorizontal),
         m_userScrollableVertical(userScrollableVertical),
-        m_mainThreadScrollingReasons(mainThreadScrollingReasons) {}
+        m_mainThreadScrollingReasons(mainThreadScrollingReasons),
+        m_scrollClient(scrollClient) {}
 
   RefPtr<const ScrollPaintPropertyNode> m_parent;
   IntSize m_clip;
   IntSize m_bounds;
   bool m_userScrollableHorizontal : 1;
   bool m_userScrollableVertical : 1;
   MainThreadScrollingReasons m_mainThreadScrollingReasons;
+  WebLayerScrollClient* m_scrollClient;
 };
 
 // Redeclared here to avoid ODR issues.
 // See platform/testing/PaintPrinters.h.
 void PrintTo(const ScrollPaintPropertyNode&, std::ostream*);
 
 }  // namespace blink
 
 #endif  // ScrollPaintPropertyNode_h