Revert of Divorce PaintInvalidationState from LayoutState (https://codereview.chromium.org/36083300…

Source/core/rendering/LayoutState.h

 /*
  * Copyright (C) 2007 Apple Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 37 matching lines @@
     explicit LayoutState(RenderObject& root);
 
     LayoutState(RenderBox&, const LayoutSize& offset, LayoutUnit pageLogicalHeight = 0, bool pageHeightLogicalChanged = false, ColumnInfo* = 0);
     LayoutState(RenderInline&);
 
     ~LayoutState();
 
     void clearPaginationInformation();
     bool isPaginatingColumns() const { return m_columnInfo; }
     bool isPaginated() const { return m_isPaginated; }
+    bool isClipped() const { return m_clipped; }
 
     // The page logical offset is the object's offset from the top of the page in the page progression
     // direction (so an x-offset in vertical text and a y-offset for horizontal text).
     LayoutUnit pageLogicalOffset(const RenderBox&, const LayoutUnit& childLogicalOffset) const;
 
     void addForcedColumnBreak(const RenderBox&, const LayoutUnit& childLogicalOffset);
 
     void setColumnInfo(ColumnInfo* columnInfo) { m_columnInfo = columnInfo; }
 
     const LayoutSize& layoutOffset() const { return m_layoutOffset; }
     const LayoutSize& pageOffset() const { return m_pageOffset; }
     LayoutUnit pageLogicalHeight() const { return m_pageLogicalHeight; }
     bool pageLogicalHeightChanged() const { return m_pageLogicalHeightChanged; }
 
     LayoutState* next() const { return m_next; }
 
     bool needsBlockDirectionLocationSetBeforeLayout() const { return m_isPaginated && m_pageLogicalHeight; }
 
     ColumnInfo* columnInfo() const { return m_columnInfo; }
 
+    bool cachedOffsetsEnabled() const { return m_cachedOffsetsEnabled; }
+
+    const LayoutRect& clipRect() const
+    {
+        ASSERT(m_cachedOffsetsEnabled);
+        return m_clipRect;
+    }
+    const LayoutSize& paintOffset() const
+    {
+        ASSERT(m_cachedOffsetsEnabled);
+        return m_paintOffset;
+    }
+
     RenderObject& renderer() const { return m_renderer; }
 
 private:
     friend class ForceHorriblySlowRectMapping;
 
     // Do not add anything apart from bitfields until after m_columnInfo. See https://bugs.webkit.org/show_bug.cgi?id=100173
-    bool m_isPaginated : 1;
+    bool m_clipped:1;
+    bool m_isPaginated:1;
     // If our page height has changed, this will force all blocks to relayout.
-    bool m_pageLogicalHeightChanged : 1;
+    bool m_pageLogicalHeightChanged:1;
 
+    bool m_cachedOffsetsEnabled:1;
     // If the enclosing pagination model is a column model, then this will store column information for easy retrieval/manipulation.
     ColumnInfo* m_columnInfo;
     LayoutState* m_next;
 
+    // FIXME: Distinguish between the layout clip rect and the paint clip rect which may be larger,
+    // e.g., because of composited scrolling.
+    LayoutRect m_clipRect;
+
+    // x/y offset from container. Includes relative positioning and scroll offsets.
+    LayoutSize m_paintOffset;
     // x/y offset from container. Does not include relative positioning or scroll offsets.
     LayoutSize m_layoutOffset;
 
     // The current page height for the pagination model that encloses us.
     LayoutUnit m_pageLogicalHeight;
     // The offset of the start of the first page in the nearest enclosing pagination model.
     LayoutSize m_pageOffset;
 
     RenderObject& m_renderer;
 };
 
 } // namespace WebCore
 
 #endif // LayoutState_h