[CSS Grid Layout] Replace the usage of pointers to functions

Source/core/layout/LayoutGrid.h

Index: Source/core/layout/LayoutGrid.h
diff --git a/Source/core/layout/LayoutGrid.h b/Source/core/layout/LayoutGrid.h
index d138a24722d7461a46b9421abe5935f6d20836f6..95e50304e3446aeb0405d2c64218880cb818670d 100644
--- a/Source/core/layout/LayoutGrid.h
+++ b/Source/core/layout/LayoutGrid.h
@@ -99,13 +99,26 @@ private:
     void offsetAndBreadthForPositionedChild(const LayoutBox&, GridTrackSizingDirection, bool startIsAuto, bool endIsAuto, LayoutUnit& offset, LayoutUnit& breadth);
     void populateGridPositions(const GridSizingData&);
 
-    typedef LayoutUnit (LayoutGrid::* SizingFunction)(LayoutBox&, GridTrackSizingDirection, Vector<GridTrack>&);
-    typedef const LayoutUnit& (GridTrack::* AccumulatorGetter)() const;
-    typedef bool (GridTrackSize::* FilterFunction)() const;
+    enum TrackSizeRestriction {
+        AllowInfinity,
+        ForbidInfinity,
+    };
+    enum TrackSizeComputationPhase {
+        ResolveIntrinsicMinimums,
+        ResolveMaxContentMinimums,
+        ResolveIntrinsicMaximums,
+        ResolveMaxContentMaximums,
+        MaximizeTracks,
+    };
+    static const LayoutUnit& trackSizeForTrackSizeComputationPhase(TrackSizeComputationPhase, GridTrack&, TrackSizeRestriction);

[cbiesinger, 2015/04/30 23:33:01]

So the patch looks good except that I don't see any place where you pass in
AllowInfinity here? What am I missing?

[dsinclair, 2015/05/08 15:50:28]

Can GridTrack be const?

[svillar, 2015/05/11 07:11:45]

Acknowledged.

+    static bool shouldProcessTrackForTrackSizeComputationPhase(TrackSizeComputationPhase, const GridTrackSize&);

[dsinclair, 2015/05/08 15:50:27]

These are only called in this class, and don't seem like they use class
knowledge, can they be moved to an anonymous namespace inside the .cpp file?

[svillar, 2015/05/11 07:11:45]

Sure.

+    static bool trackShouldGrowBeyondGrowthLimitsForTrackSizeComputationPhase(TrackSizeComputationPhase, const GridTrackSize&);
+    static void updateTrackSizeForTrackSizeComputationPhase(TrackSizeComputationPhase, GridTrack&);

[dsinclair, 2015/05/08 15:50:28]

Can GridTrack be const?

[svillar, 2015/05/11 07:11:45]

Acknowledged.

     typedef struct GridItemsSpanGroupRange GridItemsSpanGroupRange;
+    LayoutUnit currentItemSizeForTrackSizeComputationPhase(TrackSizeComputationPhase, LayoutBox&, GridTrackSizingDirection, Vector<GridTrack>& columnTracks);
     void resolveContentBasedTrackSizingFunctionsForNonSpanningItems(GridTrackSizingDirection, const GridCoordinate&, LayoutBox& gridItem, GridTrack&, Vector<GridTrack>& columnTracks);
-    void resolveContentBasedTrackSizingFunctionsForItems(GridTrackSizingDirection, GridSizingData&, const GridItemsSpanGroupRange&, FilterFunction, SizingFunction, AccumulatorGetter, AccumulatorGrowFunction, FilterFunction growAboveMaxBreadthFilterFunction = nullptr);
-    void distributeSpaceToTracks(Vector<GridTrack*>&, const Vector<GridTrack*>* growBeyondGrowthLimitsTracks, AccumulatorGetter, GridSizingData&, LayoutUnit& availableLogicalSpace);
+    template <TrackSizeComputationPhase> void resolveContentBasedTrackSizingFunctionsForItems(GridTrackSizingDirection, GridSizingData&, const GridItemsSpanGroupRange&);
+    template <TrackSizeComputationPhase> void distributeSpaceToTracks(Vector<GridTrack*>&, const Vector<GridTrack*>* growBeyondGrowthLimitsTracks, GridSizingData&, LayoutUnit& availableLogicalSpace);

[dsinclair, 2015/05/08 15:50:27]

Why template these and not just pass in TrackSizeComputationPhase as a
parameter?

[svillar, 2015/05/11 07:11:45]

The reason why I used templates is because we always explicitly call them with a
given phase, it isn't that we compute a parameter and pass it to the function. 

They will obviously be equivalent but having a template makes IMO it more
explicit the four phases of the computation.

 
     double computeNormalizedFractionBreadth(Vector<GridTrack>&, const GridSpan& tracksSpan, GridTrackSizingDirection, LayoutUnit availableLogicalSpace) const;