[CSS Grid Layout] Fix positioned grid children position and size

Source/core/rendering/RenderBox.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 165 matching lines @@
     FloatQuad absoluteContentQuad() const;
 
     // This returns the content area of the box (excluding padding and border). The only difference with contentBoxRect is that computedCSSContentBoxRect
     // does include the intrinsic padding in the content box as this is what some callers expect (like getComputedStyle).
     LayoutRect computedCSSContentBoxRect() const { return LayoutRect(borderLeft() + computedCSSPaddingLeft(), borderTop() + computedCSSPaddingTop(), clientWidth() - computedCSSPaddingLeft() - computedCSSPaddingRight(), clientHeight() - computedCSSPaddingTop() - computedCSSPaddingBottom()); }
 
     virtual void addFocusRingRects(Vector<LayoutRect>&, const LayoutPoint& additionalOffset) const override;
 
     // Use this with caution! No type checking is done!
     RenderBox* previousSiblingBox() const;
+    RenderBox* previousInFlowSiblingBox() const;
     RenderBox* nextSiblingBox() const;
+    RenderBox* nextInFlowSiblingBox() const;
     RenderBox* parentBox() const;
 
     bool canResize() const;
 
     // Visual and layout overflow are in the coordinate space of the box.  This means that they aren't purely physical directions.
     // For horizontal-tb and vertical-lr they will match physical directions, but for horizontal-bt and vertical-rl, the top/bottom and left/right
     // respectively are flipped when compared to their physical counterparts.  For example minX is on the left in vertical-lr,
     // but it is on the right in vertical-rl.
     LayoutRect noOverflowRect() const;
     LayoutRect layoutOverflowRect() const { return m_overflow ? m_overflow->layoutOverflowRect() : noOverflowRect(); }
@@ skipping 145 matching lines @@
 
     LayoutUnit overrideContainingBlockContentLogicalWidth() const;
     LayoutUnit overrideContainingBlockContentLogicalHeight() const;
     bool hasOverrideContainingBlockLogicalWidth() const;
     bool hasOverrideContainingBlockLogicalHeight() const;
     void setOverrideContainingBlockContentLogicalWidth(LayoutUnit);
     void setOverrideContainingBlockContentLogicalHeight(LayoutUnit);
     void clearContainingBlockOverrideSize();
     void clearOverrideContainingBlockContentLogicalHeight();
 
+    LayoutUnit overrideInlineOffset() const;
+    LayoutUnit overrideBlockOffset() const;
+    bool hasOverrideInlineOffset() const;
+    bool hasOverrideBlockOffset() const;
+    void setOverrideInlineOffset(LayoutUnit inlineOffest);
+    void setOverrideBlockOffset(LayoutUnit blockOffest);
+    void clearOverrideInlineAndBlockOffests();
+
     virtual LayoutSize offsetFromContainer(const RenderObject*, const LayoutPoint&, bool* offsetDependsOnPoint = 0) const override;
 
     LayoutUnit adjustBorderBoxLogicalWidthForBoxSizing(LayoutUnit width) const;
     LayoutUnit adjustBorderBoxLogicalHeightForBoxSizing(LayoutUnit height) const;
     LayoutUnit adjustContentBoxLogicalWidthForBoxSizing(LayoutUnit width) const;
     LayoutUnit adjustContentBoxLogicalHeightForBoxSizing(LayoutUnit height) const;
 
     struct ComputedMarginValues {
         ComputedMarginValues() { }
 
@@ skipping 405 matching lines @@
     OwnPtr<RenderBoxRareData> m_rareData;
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderBox, isBox());
 
 inline RenderBox* RenderBox::previousSiblingBox() const
 {
     return toRenderBox(previousSibling());
 }
 
+inline RenderBox* RenderBox::previousInFlowSiblingBox() const
+{
+    RenderBox* previous = previousSiblingBox();
+    while (previous && previous->isOutOfFlowPositioned())
+        previous = previous->previousSiblingBox();
+    return previous;
+}
+
 inline RenderBox* RenderBox::nextSiblingBox() const
 {
     return toRenderBox(nextSibling());
 }
 
+inline RenderBox* RenderBox::nextInFlowSiblingBox() const
+{
+    RenderBox* next = nextSiblingBox();
+    while (next && next->isOutOfFlowPositioned())
+        next = next->nextSiblingBox();
+    return next;
+}
+
 inline RenderBox* RenderBox::parentBox() const
 {
     return toRenderBox(parent());
 }
 
 inline RenderBox* RenderBox::firstChildBox() const
 {
     return toRenderBox(slowFirstChild());
 }
 
@@ skipping 13 matching lines @@
         if (UNLIKELY(inlineBoxWrapper() != 0))
             deleteLineBoxWrapper();
     }
 
     ensureRareData().m_inlineBoxWrapper = boxWrapper;
 }
 
 } // namespace blink
 
 #endif // RenderBox_h