Move painting code from RenderGrid to GridPainter.

Source/core/rendering/RenderGrid.cpp

Index: Source/core/rendering/RenderGrid.cpp
diff --git a/Source/core/rendering/RenderGrid.cpp b/Source/core/rendering/RenderGrid.cpp
index c68a38e806b46ec32173c3d9a6a4f32e92080af7..40f2d1e2ac51956f535803cef84a2da8f2d36154 100644
--- a/Source/core/rendering/RenderGrid.cpp
+++ b/Source/core/rendering/RenderGrid.cpp
@@ -26,6 +26,7 @@
 #include "config.h"
 #include "core/rendering/RenderGrid.h"
 
+#include "core/paint/GridPainter.h"
 #include "core/rendering/RenderLayer.h"
 #include "core/rendering/RenderView.h"
 #include "core/rendering/TextAutosizer.h"
@@ -1379,80 +1380,9 @@ LayoutPoint RenderGrid::findChildLogicalPosition(const RenderBox& child) const
     return LayoutPoint(columnPositionForChild(child), rowPositionForChild(child));
 }
 
-static GridSpan dirtiedGridAreas(const Vector<LayoutUnit>& coordinates, LayoutUnit start, LayoutUnit end)
-{
-    // This function does a binary search over the coordinates.
-    // This doesn't work with grid items overflowing their grid areas, but that is managed with m_gridItemsOverflowingGridArea.
-
-    size_t startGridAreaIndex = std::upper_bound(coordinates.begin(), coordinates.end() - 1, start) - coordinates.begin();
-    if (startGridAreaIndex > 0)
-        --startGridAreaIndex;
-
-    size_t endGridAreaIndex = std::upper_bound(coordinates.begin() + startGridAreaIndex, coordinates.end() - 1, end) - coordinates.begin();
-    if (endGridAreaIndex > 0)
-        --endGridAreaIndex;
-
-    return GridSpan(startGridAreaIndex, endGridAreaIndex);
-}
-
-class GridItemsSorter {
-public:
-    bool operator()(const std::pair<RenderBox*, size_t>& firstChild, const std::pair<RenderBox*, size_t>& secondChild) const
-    {
-        if (firstChild.first->style()->order() != secondChild.first->style()->order())
-            return firstChild.first->style()->order() < secondChild.first->style()->order();
-
-        return firstChild.second < secondChild.second;
-    }
-};
-
 void RenderGrid::paintChildren(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
-    ASSERT_WITH_SECURITY_IMPLICATION(!gridIsDirty());
-
-    LayoutRect localPaintInvalidationRect = paintInfo.rect;
-    localPaintInvalidationRect.moveBy(-paintOffset);
-
-    GridSpan dirtiedColumns = dirtiedGridAreas(m_columnPositions, localPaintInvalidationRect.x(), localPaintInvalidationRect.maxX());
-    GridSpan dirtiedRows = dirtiedGridAreas(m_rowPositions, localPaintInvalidationRect.y(), localPaintInvalidationRect.maxY());
-
-    Vector<std::pair<RenderBox*, size_t> > gridItemsToBePainted;
-
-    for (GridSpan::iterator row = dirtiedRows.begin(); row != dirtiedRows.end(); ++row) {
-        for (GridSpan::iterator column = dirtiedColumns.begin(); column != dirtiedColumns.end(); ++column) {
-            const Vector<RenderBox*, 1>& children = m_grid[row.toInt()][column.toInt()];
-            for (size_t j = 0; j < children.size(); ++j)
-                gridItemsToBePainted.append(std::make_pair(children[j], m_gridItemsIndexesMap.get(children[j])));
-        }
-    }
-
-    for (Vector<RenderBox*>::const_iterator it = m_gridItemsOverflowingGridArea.begin(); it != m_gridItemsOverflowingGridArea.end(); ++it) {
-        if ((*it)->frameRect().intersects(localPaintInvalidationRect))
-            gridItemsToBePainted.append(std::make_pair(*it, m_gridItemsIndexesMap.get(*it)));
-    }
-
-    // Sort grid items following order-modified document order.
-    // See http://www.w3.org/TR/css-flexbox/#order-modified-document-order
-    std::stable_sort(gridItemsToBePainted.begin(), gridItemsToBePainted.end(), GridItemsSorter());
-
-    RenderBox* previous = 0;
-    for (Vector<std::pair<RenderBox*, size_t> >::const_iterator it = gridItemsToBePainted.begin(); it != gridItemsToBePainted.end(); ++it) {
-        // We might have duplicates because of spanning children are included in all cells they span.
-        // Skip them here to avoid painting items several times.
-        RenderBox* current = (*it).first;
-        if (current == previous)
-            continue;
-
-        paintChild(current, paintInfo, paintOffset);
-        previous = current;
-    }
-}
-
-void RenderGrid::paintChild(RenderBox* child, PaintInfo& paintInfo, const LayoutPoint& paintOffset)
-{
-    LayoutPoint childPoint = flipForWritingModeForChild(child, paintOffset);
-    if (!child->hasSelfPaintingLayer() && !child->isFloating())
-        child->paint(paintInfo, childPoint);
+    GridPainter(*this).paintChildren(paintInfo, paintOffset);
 }
 
 const char* RenderGrid::renderName() const