[CSS Grid Layout] Store m_grid across layout

Source/core/rendering/RenderBox.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. 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
@@ skipping 29 matching lines @@
 #include "core/page/Page.h"
 #include "core/platform/graphics/FloatQuad.h"
 #include "core/platform/graphics/GraphicsContextStateSaver.h"
 #include "core/platform/graphics/transforms/TransformState.h"
 #include "core/rendering/HitTestResult.h"
 #include "core/rendering/PaintInfo.h"
 #include "core/rendering/RenderBoxRegionInfo.h"
 #include "core/rendering/RenderFlexibleBox.h"
 #include "core/rendering/RenderFlowThread.h"
 #include "core/rendering/RenderGeometryMap.h"
+#include "core/rendering/RenderGrid.h"
 #include "core/rendering/RenderInline.h"
 #include "core/rendering/RenderLayer.h"
 #include "core/rendering/RenderLayerCompositor.h"
 #include "core/rendering/RenderListMarker.h"
 #include "core/rendering/RenderRegion.h"
 #include "core/rendering/RenderTableCell.h"
 #include "core/rendering/RenderTheme.h"
 #include "core/rendering/RenderView.h"
 
 using namespace std;
@@ skipping 238 matching lines @@
                 document()->documentElement()->renderer()->style()->setWritingMode(newStyle->writingMode());
                 document()->documentElement()->renderer()->setHorizontalWritingMode(newStyle->isHorizontalWritingMode());
             }
             setNeedsLayoutAndPrefWidthsRecalc();
         }
 
         frame()->view()->recalculateScrollbarOverlayStyle();
     }
 
     updateShapeOutsideInfoAfterStyleChange(style()->shapeOutside(), oldStyle ? oldStyle->shapeOutside() : 0);
+    updateGridPositionAfterStyleChange(oldStyle);
 }
 
 void RenderBox::updateShapeOutsideInfoAfterStyleChange(const ShapeValue* shapeOutside, const ShapeValue* oldShapeOutside)
 {
     // FIXME: A future optimization would do a deep comparison for equality. (bug 100811)
     if (shapeOutside == oldShapeOutside)
         return;
 
     if (shapeOutside) {
         ShapeOutsideInfo* shapeOutsideInfo = ShapeOutsideInfo::ensureInfo(this);
         shapeOutsideInfo->dirtyShapeSize();
     } else {
         ShapeOutsideInfo::removeInfo(this);
     }
 }
 
+void RenderBox::updateGridPositionAfterStyleChange(const RenderStyle* oldStyle)
+{
+    if (!oldStyle || !parent() || !parent()->isRenderGrid())
+        return;
+
+    if (oldStyle->gridColumnStart() == style()->gridColumnStart()
+        && oldStyle->gridColumnEnd() == style()->gridColumnEnd()
+        && oldStyle->gridRowStart() == style()->gridRowStart()
+        && oldStyle->gridRowEnd() == style()->gridRowEnd()
+        && oldStyle->order() == style()->order())
+        return;
+
+    // It should be possible to not dirty the grid in some cases (like moving an explicitly placed grid item).
+    // For now, it's more simple to just always recompute the grid.
+    toRenderGrid(parent())->dirtyGrid();
+}
+
 void RenderBox::updateFromStyle()
 {
     RenderBoxModelObject::updateFromStyle();
 
     RenderStyle* styleToUse = style();
     bool isRootObject = isRoot();
     bool isViewObject = isRenderView();
 
     // The root and the RenderView always paint their backgrounds/borders.
     if (isRootObject || isViewObject)
@@ skipping 4336 matching lines @@
     }
 
     if (didSplitParentAnonymousBoxes)
         markBoxForRelayoutAfterSplit(this);
 
     ASSERT(beforeChild->parent() == this);
     return beforeChild;
 }
 
 } // namespace WebCore