Unify all types of overflow-related clips for paint and hit testing.

third_party/WebKit/Source/core/layout/LayoutBox.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2006, 2007 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 1040 matching lines @@
     AvoidBreaks    // Preferably avoid breaks. If not possible, examine children
                    // to find possible break points.
   };
   virtual PaginationBreakability getPaginationBreakability() const;
 
   LayoutRect localCaretRect(
       InlineBox*,
       int caretOffset,
       LayoutUnit* extraWidthToEndOfLine = nullptr) override;
 
+  // Returns whether content which overflows should be clipped. This is not just
+  // because of overflow clip, but other types of clip as well, such as
+  // control clips or contain: paint.
+  virtual bool shouldClipOverflow() const;
+
+  // Returns the intersection of all overflow clips which apply.
   virtual LayoutRect overflowClipRect(
       const LayoutPoint& location,
       OverlayScrollbarClipBehavior = IgnoreOverlayScrollbarSize) const;
   LayoutRect clipRect(const LayoutPoint& location) const;
-  virtual bool hasControlClip() const { return false; }
-  virtual LayoutRect controlClipRect(const LayoutPoint&) const {
-    return LayoutRect();
-  }
 
   // Returns the combination of overflow clip, contain: paint clip and CSS clip
   // for this object, in local space.
   LayoutRect clippingRect() const;
 
   virtual void paintBoxDecorationBackground(const PaintInfo&,
                                             const LayoutPoint&) const;
   virtual void paintMask(const PaintInfo&, const LayoutPoint&) const;
   void imageChanged(WrappedImagePtr, const IntRect* = nullptr) override;
   ResourcePriority computeResourcePriority() const final;
@@ skipping 219 matching lines @@
   bool mustInvalidateBackgroundOrBorderPaintOnHeightChange() const;
   bool mustInvalidateBackgroundOrBorderPaintOnWidthChange() const;
 
   // Returns true if the box intersects the viewport visible to the user.
   bool intersectsVisibleViewport() const;
 
   bool hasNonCompositedScrollbars() const final;
 
   void ensureIsReadyForPaintInvalidation() override;
 
-  virtual bool shouldClipOverflow() const;
+  virtual bool hasControlClip() const { return false; }
 
  protected:
+  virtual LayoutRect controlClipRect(const LayoutPoint&) const {
+    return LayoutRect();
+  }
+
   void willBeDestroyed() override;
 
   void insertedIntoTree() override;
   void willBeRemovedFromTree() override;
 
   void styleWillChange(StyleDifference, const ComputedStyle& newStyle) override;
   void styleDidChange(StyleDifference, const ComputedStyle* oldStyle) override;
   void updateFromStyle() override;
 
   virtual ItemPosition selfAlignmentNormalBehavior() const {
@@ skipping 304 matching lines @@
 
 inline bool LayoutBox::isForcedFragmentainerBreakValue(EBreak breakValue) {
   return breakValue == BreakColumn || breakValue == BreakLeft ||
          breakValue == BreakPage || breakValue == BreakRecto ||
          breakValue == BreakRight || breakValue == BreakVerso;
 }
 
 }  // namespace blink
 
 #endif  // LayoutBox_h