[css-grid] Get rid of GridResolvedPosition

third_party/WebKit/Source/core/layout/LayoutGrid.cpp

 /*
  * Copyright (C) 2011 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 529 matching lines @@
     } else {
         for (const auto& trackIndex : flexibleSizedTracksIndex)
             flexFraction = std::max(flexFraction, normalizedFlexFraction(tracks[trackIndex], gridTrackSize(direction, trackIndex).maxTrackBreadth().flex()));
 
         for (size_t i = 0; i < flexibleSizedTracksIndex.size(); ++i) {
             GridIterator iterator(m_grid, direction, flexibleSizedTracksIndex[i]);
             while (LayoutBox* gridItem = iterator.nextGridItem()) {
                 const GridSpan span = cachedGridSpan(*gridItem, direction);
 
                 // Do not include already processed items.
-                if (i > 0 && span.resolvedInitialPosition().toInt() <= flexibleSizedTracksIndex[i - 1])
+                if (i > 0 && span.resolvedInitialPosition() <= flexibleSizedTracksIndex[i - 1])
                     continue;
 
                 flexFraction = std::max(flexFraction, findFlexFactorUnitSize(tracks, span, direction, maxContentForChild(*gridItem, direction, sizingData.columnTracks)));
             }
         }
     }
 
     for (const auto& trackIndex : flexibleSizedTracksIndex) {
         GridTrackSize trackSize = gridTrackSize(direction, trackIndex);
 
@@ skipping 63 matching lines @@
     return hypotheticalFactorUnitSize;
 }
 
 double LayoutGrid::findFlexFactorUnitSize(const Vector<GridTrack>& tracks, const GridSpan& tracksSpan, GridTrackSizingDirection direction, LayoutUnit leftOverSpace) const
 {
     if (leftOverSpace <= 0)
         return 0;
 
     double flexFactorSum = 0;
     Vector<size_t, 8> flexibleTracksIndexes;
-    for (const auto& resolvedPosition : tracksSpan) {
-        size_t trackIndex = resolvedPosition.toInt();
+    for (const auto& trackIndex : tracksSpan) {
         GridTrackSize trackSize = gridTrackSize(direction, trackIndex);
         if (!trackSize.maxTrackBreadth().isFlex()) {
             leftOverSpace -= tracks[trackIndex].baseSize();
         } else {
             flexibleTracksIndexes.append(trackIndex);
             flexFactorSum += trackSize.maxTrackBreadth().flex();
         }
     }
 
     // The function is not called if we don't have <flex> grid tracks
@@ skipping 132 matching lines @@
     bool operator<(const GridItemWithSpan other) const { return m_gridSpan.integerSpan() < other.m_gridSpan.integerSpan(); }
 
 private:
     LayoutBox* m_gridItem;
     GridSpan m_gridSpan;
 };
 
 bool LayoutGrid::spanningItemCrossesFlexibleSizedTracks(const GridSpan& span, GridTrackSizingDirection direction) const
 {
     for (const auto& trackPosition : span) {
-        const GridTrackSize& trackSize = gridTrackSize(direction, trackPosition.toInt());
+        const GridTrackSize& trackSize = gridTrackSize(direction, trackPosition);
         if (trackSize.minTrackBreadth().isFlex() || trackSize.maxTrackBreadth().isFlex())
             return true;
     }
 
     return false;
 }
 
 void LayoutGrid::resolveContentBasedTrackSizingFunctions(GridTrackSizingDirection direction, GridSizingData& sizingData)
 {
     sizingData.itemsSortedByIncreasingSpan.shrink(0);
@@ skipping 28 matching lines @@
 
     for (const auto& trackIndex : sizingData.contentSizedTracksIndex) {
         GridTrack& track = (direction == ForColumns) ? sizingData.columnTracks[trackIndex] : sizingData.rowTracks[trackIndex];
         if (track.growthLimitIsInfinite())
             track.setGrowthLimit(track.baseSize());
     }
 }
 
 void LayoutGrid::resolveContentBasedTrackSizingFunctionsForNonSpanningItems(GridTrackSizingDirection direction, const GridSpan& span, LayoutBox& gridItem, GridTrack& track, Vector<GridTrack>& columnTracks)
 {
-    const GridResolvedPosition trackPosition = span.resolvedInitialPosition();
-    GridTrackSize trackSize = gridTrackSize(direction, trackPosition.toInt());
+    const size_t trackPosition = span.resolvedInitialPosition();
+    GridTrackSize trackSize = gridTrackSize(direction, trackPosition);
 
     if (trackSize.hasMinContentMinTrackBreadth())
         track.setBaseSize(std::max(track.baseSize(), minContentForChild(gridItem, direction, columnTracks)));
     else if (trackSize.hasMaxContentMinTrackBreadth())
         track.setBaseSize(std::max(track.baseSize(), maxContentForChild(gridItem, direction, columnTracks)));
     else if (trackSize.hasAutoMinTrackBreadth())
         track.setBaseSize(std::max(track.baseSize(), minSizeForChild(gridItem, direction, columnTracks)));
 
     if (trackSize.hasMinContentMaxTrackBreadth())
         track.setGrowthLimit(std::max(track.growthLimit(), minContentForChild(gridItem, direction, columnTracks)));
@@ skipping 137 matching lines @@
 
     for (auto it = gridItemsWithSpan.rangeStart; it != gridItemsWithSpan.rangeEnd; ++it) {
         GridItemWithSpan& gridItemWithSpan = *it;
         ASSERT(gridItemWithSpan.gridSpan().integerSpan() > 1);
         const GridSpan& itemSpan = gridItemWithSpan.gridSpan();
 
         sizingData.growBeyondGrowthLimitsTracks.shrink(0);
         sizingData.filteredTracks.shrink(0);
         LayoutUnit spanningTracksSize;
         for (const auto& trackPosition : itemSpan) {
-            GridTrackSize trackSize = gridTrackSize(direction, trackPosition.toInt());
-            GridTrack& track = (direction == ForColumns) ? sizingData.columnTracks[trackPosition.toInt()] : sizingData.rowTracks[trackPosition.toInt()];
+            GridTrackSize trackSize = gridTrackSize(direction, trackPosition);
+            GridTrack& track = (direction == ForColumns) ? sizingData.columnTracks[trackPosition] : sizingData.rowTracks[trackPosition];
             spanningTracksSize += trackSizeForTrackSizeComputationPhase(phase, track, ForbidInfinity);
             if (!shouldProcessTrackForTrackSizeComputationPhase(phase, trackSize))
                 continue;
 
             sizingData.filteredTracks.append(&track);
 
             if (trackShouldGrowBeyondGrowthLimitsForTrackSizeComputationPhase(phase, trackSize))
                 sizingData.growBeyondGrowthLimitsTracks.append(&track);
         }
 
@@ skipping 91 matching lines @@
 
     if (maximumColumnSize > gridColumnCount()) {
         for (size_t row = 0; row < gridRowCount(); ++row)
             m_grid[row].grow(maximumColumnSize);
     }
 }
 
 void LayoutGrid::insertItemIntoGrid(LayoutBox& child, const GridCoordinate& coordinate)
 {
     RELEASE_ASSERT(coordinate.rows.isDefinite() && coordinate.columns.isDefinite());
-    ensureGridSize(coordinate.rows.resolvedFinalPosition().toInt(), coordinate.columns.resolvedFinalPosition().toInt());
+    ensureGridSize(coordinate.rows.resolvedFinalPosition(), coordinate.columns.resolvedFinalPosition());
 
-    for (GridSpan::iterator row = coordinate.rows.begin(); row != coordinate.rows.end(); ++row) {
-        for (GridSpan::iterator column = coordinate.columns.begin(); column != coordinate.columns.end(); ++column)
-            m_grid[row.toInt()][column.toInt()].append(&child);
+    for (const auto& row : coordinate.rows) {
+        for (const auto& column: coordinate.columns)
+            m_grid[row][column].append(&child);
     }
 }
 
 void LayoutGrid::placeItemsOnGrid()
 {
     if (!m_gridIsDirty)
         return;
 
     ASSERT(m_gridItemCoordinate.isEmpty());
 
@@ skipping 55 matching lines @@
         populator.collectChild(child);
         m_gridItemsIndexesMap.set(child, childIndex++);
 
         // This function bypasses the cache (cachedGridCoordinate()) as it is used to build it.
         GridSpan rowPositions = GridResolvedPosition::resolveGridPositionsFromStyle(*style(), *child, ForRows);
         GridSpan columnPositions = GridResolvedPosition::resolveGridPositionsFromStyle(*style(), *child, ForColumns);
         m_gridItemCoordinate.set(child, GridCoordinate(rowPositions, columnPositions));
 
         // |positions| is 0 if we need to run the auto-placement algorithm.
         if (rowPositions.isDefinite()) {
-            maximumRowIndex = std::max<size_t>(maximumRowIndex, rowPositions.resolvedFinalPosition().toInt());
+            maximumRowIndex = std::max<size_t>(maximumRowIndex, rowPositions.resolvedFinalPosition());
         } else {
             // Grow the grid for items with a definite row span, getting the largest such span.
-            GridSpan positions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), *child, ForRows, GridResolvedPosition(0));
-            maximumRowIndex = std::max<size_t>(maximumRowIndex, positions.resolvedFinalPosition().toInt());
+            GridSpan positions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), *child, ForRows, 0);
+            maximumRowIndex = std::max<size_t>(maximumRowIndex, positions.resolvedFinalPosition());
         }
 
         if (columnPositions.isDefinite()) {
-            maximumColumnIndex = std::max<size_t>(maximumColumnIndex, columnPositions.resolvedFinalPosition().toInt());
+            maximumColumnIndex = std::max<size_t>(maximumColumnIndex, columnPositions.resolvedFinalPosition());
         } else {
             // Grow the grid for items with a definite column span, getting the largest such span.
-            GridSpan positions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), *child, ForColumns, GridResolvedPosition(0));
-            maximumColumnIndex = std::max<size_t>(maximumColumnIndex, positions.resolvedFinalPosition().toInt());
+            GridSpan positions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), *child, ForColumns, 0);
+            maximumColumnIndex = std::max<size_t>(maximumColumnIndex, positions.resolvedFinalPosition());
         }
     }
 
     m_grid.grow(maximumRowIndex);
     for (auto& column : m_grid)
         column.grow(maximumColumnIndex);
 }
 
 PassOwnPtr<GridCoordinate> LayoutGrid::createEmptyGridAreaAtSpecifiedPositionsOutsideGrid(const LayoutBox& gridItem, GridTrackSizingDirection specifiedDirection, const GridSpan& specifiedPositions) const
 {
     GridTrackSizingDirection crossDirection = specifiedDirection == ForColumns ? ForRows : ForColumns;
     const size_t endOfCrossDirection = crossDirection == ForColumns ? gridColumnCount() : gridRowCount();
-    GridSpan crossDirectionPositions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), gridItem, crossDirection, GridResolvedPosition(endOfCrossDirection));
+    GridSpan crossDirectionPositions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), gridItem, crossDirection, endOfCrossDirection);
     return adoptPtr(new GridCoordinate(specifiedDirection == ForColumns ? crossDirectionPositions : specifiedPositions, specifiedDirection == ForColumns ? specifiedPositions : crossDirectionPositions));
 }
 
 void LayoutGrid::placeSpecifiedMajorAxisItemsOnGrid(const Vector<LayoutBox*>& autoGridItems)
 {
     bool isForColumns = autoPlacementMajorAxisDirection() == ForColumns;
     bool isGridAutoFlowDense = style()->isGridAutoFlowAlgorithmDense();
 
     // Mapping between the major axis tracks (rows or columns) and the last auto-placed item's position inserted on
     // that track. This is needed to implement "sparse" packing for items locked to a given track.
     // See http://dev.w3.org/csswg/css-grid/#auto-placement-algo
     HashMap<unsigned, unsigned, DefaultHash<unsigned>::Hash, WTF::UnsignedWithZeroKeyHashTraits<unsigned>> minorAxisCursors;
 
     for (const auto& autoGridItem : autoGridItems) {
         GridSpan majorAxisPositions = cachedGridSpan(*autoGridItem, autoPlacementMajorAxisDirection());
         ASSERT(majorAxisPositions.isDefinite());
         ASSERT(!cachedGridSpan(*autoGridItem, autoPlacementMinorAxisDirection()).isDefinite());
-        GridSpan minorAxisPositions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), *autoGridItem, autoPlacementMinorAxisDirection(), GridResolvedPosition(0));
-        unsigned majorAxisInitialPosition = majorAxisPositions.resolvedInitialPosition().toInt();
+        GridSpan minorAxisPositions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), *autoGridItem, autoPlacementMinorAxisDirection(), 0);
+        unsigned majorAxisInitialPosition = majorAxisPositions.resolvedInitialPosition();
 
-        GridIterator iterator(m_grid, autoPlacementMajorAxisDirection(), majorAxisPositions.resolvedInitialPosition().toInt(), isGridAutoFlowDense ? 0 : minorAxisCursors.get(majorAxisInitialPosition));
+        GridIterator iterator(m_grid, autoPlacementMajorAxisDirection(), majorAxisPositions.resolvedInitialPosition(), isGridAutoFlowDense ? 0 : minorAxisCursors.get(majorAxisInitialPosition));
         OwnPtr<GridCoordinate> emptyGridArea = iterator.nextEmptyGridArea(majorAxisPositions.integerSpan(), minorAxisPositions.integerSpan());
         if (!emptyGridArea)
             emptyGridArea = createEmptyGridAreaAtSpecifiedPositionsOutsideGrid(*autoGridItem, autoPlacementMajorAxisDirection(), majorAxisPositions);
 
         m_gridItemCoordinate.set(autoGridItem, *emptyGridArea);
         insertItemIntoGrid(*autoGridItem, *emptyGridArea);
 
         if (!isGridAutoFlowDense)
-            minorAxisCursors.set(majorAxisInitialPosition, isForColumns ? emptyGridArea->rows.resolvedInitialPosition().toInt() : emptyGridArea->columns.resolvedInitialPosition().toInt());
+            minorAxisCursors.set(majorAxisInitialPosition, isForColumns ? emptyGridArea->rows.resolvedInitialPosition() : emptyGridArea->columns.resolvedInitialPosition());
     }
 }
 
 void LayoutGrid::placeAutoMajorAxisItemsOnGrid(const Vector<LayoutBox*>& autoGridItems)
 {
     std::pair<size_t, size_t> autoPlacementCursor = std::make_pair(0, 0);
     bool isGridAutoFlowDense = style()->isGridAutoFlowAlgorithmDense();
 
     for (const auto& autoGridItem : autoGridItems) {
         placeAutoMajorAxisItemOnGrid(*autoGridItem, autoPlacementCursor);
 
         // If grid-auto-flow is dense, reset auto-placement cursor.
         if (isGridAutoFlowDense) {
             autoPlacementCursor.first = 0;
             autoPlacementCursor.second = 0;
         }
     }
 }
 
 void LayoutGrid::placeAutoMajorAxisItemOnGrid(LayoutBox& gridItem, std::pair<size_t, size_t>& autoPlacementCursor)
 {
     GridSpan minorAxisPositions = cachedGridSpan(gridItem, autoPlacementMinorAxisDirection());
     ASSERT(!cachedGridSpan(gridItem, autoPlacementMajorAxisDirection()).isDefinite());
-    GridSpan majorAxisPositions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), gridItem, autoPlacementMajorAxisDirection(), GridResolvedPosition(0));
+    GridSpan majorAxisPositions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), gridItem, autoPlacementMajorAxisDirection(), 0);
 
     const size_t endOfMajorAxis = (autoPlacementMajorAxisDirection() == ForColumns) ? gridColumnCount() : gridRowCount();
     size_t majorAxisAutoPlacementCursor = autoPlacementMajorAxisDirection() == ForColumns ? autoPlacementCursor.second : autoPlacementCursor.first;
     size_t minorAxisAutoPlacementCursor = autoPlacementMajorAxisDirection() == ForColumns ? autoPlacementCursor.first : autoPlacementCursor.second;
 
     OwnPtr<GridCoordinate> emptyGridArea;
     if (minorAxisPositions.isDefinite()) {
         // Move to the next track in major axis if initial position in minor axis is before auto-placement cursor.
-        if (minorAxisPositions.resolvedInitialPosition().toInt() < minorAxisAutoPlacementCursor)
+        if (minorAxisPositions.resolvedInitialPosition() < minorAxisAutoPlacementCursor)
             majorAxisAutoPlacementCursor++;
 
         if (majorAxisAutoPlacementCursor < endOfMajorAxis) {
-            GridIterator iterator(m_grid, autoPlacementMinorAxisDirection(), minorAxisPositions.resolvedInitialPosition().toInt(), majorAxisAutoPlacementCursor);
+            GridIterator iterator(m_grid, autoPlacementMinorAxisDirection(), minorAxisPositions.resolvedInitialPosition(), majorAxisAutoPlacementCursor);
             emptyGridArea = iterator.nextEmptyGridArea(minorAxisPositions.integerSpan(), majorAxisPositions.integerSpan());
         }
 
         if (!emptyGridArea)
             emptyGridArea = createEmptyGridAreaAtSpecifiedPositionsOutsideGrid(gridItem, autoPlacementMinorAxisDirection(), minorAxisPositions);
     } else {
-        GridSpan minorAxisPositions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), gridItem, autoPlacementMinorAxisDirection(), GridResolvedPosition(0));
+        GridSpan minorAxisPositions = GridResolvedPosition::resolveGridPositionsFromAutoPlacementPosition(*style(), gridItem, autoPlacementMinorAxisDirection(), 0);
 
         for (size_t majorAxisIndex = majorAxisAutoPlacementCursor; majorAxisIndex < endOfMajorAxis; ++majorAxisIndex) {
             GridIterator iterator(m_grid, autoPlacementMajorAxisDirection(), majorAxisIndex, minorAxisAutoPlacementCursor);
             emptyGridArea = iterator.nextEmptyGridArea(majorAxisPositions.integerSpan(), minorAxisPositions.integerSpan());
 
             if (emptyGridArea) {
                 // Check that it fits in the minor axis direction, as we shouldn't grow in that direction here (it was already managed in populateExplicitGridAndOrderIterator()).
-                GridResolvedPosition minorAxisFinalPositionIndex = autoPlacementMinorAxisDirection() == ForColumns ? emptyGridArea->columns.resolvedFinalPosition() : emptyGridArea->rows.resolvedFinalPosition();
+                size_t minorAxisFinalPositionIndex = autoPlacementMinorAxisDirection() == ForColumns ? emptyGridArea->columns.resolvedFinalPosition() : emptyGridArea->rows.resolvedFinalPosition();
                 const size_t endOfMinorAxis = autoPlacementMinorAxisDirection() == ForColumns ? gridColumnCount() : gridRowCount();
-                if (minorAxisFinalPositionIndex.toInt() <= endOfMinorAxis)
+                if (minorAxisFinalPositionIndex <= endOfMinorAxis)
                     break;
 
                 // Discard empty grid area as it does not fit in the minor axis direction.
                 // We don't need to create a new empty grid area yet as we might find a valid one in the next iteration.
                 emptyGridArea = nullptr;
             }
 
             // As we're moving to the next track in the major axis we should reset the auto-placement cursor in the minor axis.
             minorAxisAutoPlacementCursor = 0;
         }
 
         if (!emptyGridArea)
             emptyGridArea = createEmptyGridAreaAtSpecifiedPositionsOutsideGrid(gridItem, autoPlacementMinorAxisDirection(), minorAxisPositions);
     }
 
     m_gridItemCoordinate.set(&gridItem, *emptyGridArea);
     insertItemIntoGrid(gridItem, *emptyGridArea);
     // Move auto-placement cursor to the new position.
-    autoPlacementCursor.first = emptyGridArea->rows.resolvedInitialPosition().toInt();
-    autoPlacementCursor.second = emptyGridArea->columns.resolvedInitialPosition().toInt();
+    autoPlacementCursor.first = emptyGridArea->rows.resolvedInitialPosition();
+    autoPlacementCursor.second = emptyGridArea->columns.resolvedInitialPosition();
 }
 
 GridTrackSizingDirection LayoutGrid::autoPlacementMajorAxisDirection() const
 {
     return style()->isGridAutoFlowDirectionColumn() ? ForColumns : ForRows;
 }
 
 GridTrackSizingDirection LayoutGrid::autoPlacementMinorAxisDirection() const
 {
     return style()->isGridAutoFlowDirectionColumn() ? ForRows : ForColumns;
@@ skipping 82 matching lines @@
         applyStretchAlignmentToChildIfNeeded(*child);
 
         child->layoutIfNeeded();
 
         // We need pending layouts to be done in order to compute auto-margins properly.
         updateAutoMarginsInColumnAxisIfNeeded(*child);
         updateAutoMarginsInRowAxisIfNeeded(*child);
 
 #if ENABLE(ASSERT)
         const GridCoordinate& coordinate = cachedGridCoordinate(*child);
-        ASSERT(coordinate.columns.resolvedInitialPosition().toInt() < sizingData.columnTracks.size());
-        ASSERT(coordinate.rows.resolvedInitialPosition().toInt() < sizingData.rowTracks.size());
+        ASSERT(coordinate.columns.resolvedInitialPosition() < sizingData.columnTracks.size());
+        ASSERT(coordinate.rows.resolvedInitialPosition() < sizingData.rowTracks.size());
 #endif
         child->setLogicalLocation(findChildLogicalPosition(*child, sizingData));
 
         // Keep track of children overflowing their grid area as we might need to paint them even if the grid-area is
         // not visible
         if (child->logicalHeight() > overrideContainingBlockContentLogicalHeight
             || child->logicalWidth() > overrideContainingBlockContentLogicalWidth)
             m_gridItemsOverflowingGridArea.append(child);
     }
 }
@@ skipping 48 matching lines @@
         breadth = (direction == ForColumns) ? clientLogicalWidth() : clientLogicalHeight();
         return;
     }
 
     GridPosition startPosition = (direction == ForColumns) ? child.style()->gridColumnStart() : child.style()->gridRowStart();
     GridPosition endPosition = (direction == ForColumns) ? child.style()->gridColumnEnd() : child.style()->gridRowEnd();
     size_t lastTrackIndex = (direction == ForColumns ? gridColumnCount() : gridRowCount()) - 1;
 
     bool startIsAuto = startPosition.isAuto()
         || (startPosition.isNamedGridArea() && !GridResolvedPosition::isValidNamedLineOrArea(startPosition.namedGridLine(), styleRef(), GridResolvedPosition::initialPositionSide(direction)))
-        || (positions.resolvedInitialPosition().toInt() > lastTrackIndex);
+        || (positions.resolvedInitialPosition() > lastTrackIndex);
     bool endIsAuto = endPosition.isAuto()
         || (endPosition.isNamedGridArea() && !GridResolvedPosition::isValidNamedLineOrArea(endPosition.namedGridLine(), styleRef(), GridResolvedPosition::finalPositionSide(direction)))
-        || (positions.resolvedFinalPosition().prev().toInt() > lastTrackIndex);
+        || (positions.resolvedFinalPosition() - 1 > lastTrackIndex);
 
-    GridResolvedPosition firstPosition = GridResolvedPosition(0);
-    GridResolvedPosition initialPosition = startIsAuto ? firstPosition : positions.resolvedInitialPosition();
-    GridResolvedPosition lastPosition = GridResolvedPosition(lastTrackIndex);
-    GridResolvedPosition finalPosition = endIsAuto ? lastPosition : positions.resolvedFinalPosition().prev();
+    size_t firstPosition = 0;
+    size_t initialPosition = startIsAuto ? firstPosition : positions.resolvedInitialPosition();
+    size_t lastPosition = lastTrackIndex;
+    size_t finalPosition = endIsAuto ? lastPosition : positions.resolvedFinalPosition() - 1;
 
     // Positioned children do not grow the grid, so we need to clamp the positions to avoid ending up outside of it.
-    initialPosition = std::min<GridResolvedPosition>(initialPosition, lastPosition);
-    finalPosition = std::min<GridResolvedPosition>(finalPosition, lastPosition);
+    initialPosition = std::min(initialPosition, lastPosition);
+    finalPosition = std::min(finalPosition, lastPosition);
 
-    LayoutUnit start = startIsAuto ? LayoutUnit() : (direction == ForColumns) ?  m_columnPositions[initialPosition.toInt()] : m_rowPositions[initialPosition.toInt()];
-    LayoutUnit end = endIsAuto ? (direction == ForColumns) ? logicalWidth() : logicalHeight() : (direction == ForColumns) ?  m_columnPositions[finalPosition.next().toInt()] : m_rowPositions[finalPosition.next().toInt()];
+    LayoutUnit start = startIsAuto ? LayoutUnit() : (direction == ForColumns) ?  m_columnPositions[initialPosition] : m_rowPositions[initialPosition];
+    LayoutUnit end = endIsAuto ? (direction == ForColumns) ? logicalWidth() : logicalHeight() : (direction == ForColumns) ?  m_columnPositions[finalPosition + 1] : m_rowPositions[finalPosition + 1];
 
     breadth = end - start;
 
     if (startIsAuto)
         breadth -= (direction == ForColumns) ? borderStart() : borderBefore();
     else
         start -= ((direction == ForColumns) ? borderStart() : borderBefore());
 
     if (endIsAuto) {
         breadth -= (direction == ForColumns) ? borderEnd() : borderAfter();
@@ skipping 21 matching lines @@
 GridSpan LayoutGrid::cachedGridSpan(const LayoutBox& gridItem, GridTrackSizingDirection direction) const
 {
     GridCoordinate coordinate = cachedGridCoordinate(gridItem);
     return direction == ForColumns ? coordinate.columns : coordinate.rows;
 }
 
 LayoutUnit LayoutGrid::gridAreaBreadthForChild(const LayoutBox& child, GridTrackSizingDirection direction, const Vector<GridTrack>& tracks) const
 {
     const GridSpan& span = cachedGridSpan(child, direction);
     LayoutUnit gridAreaBreadth = 0;
-    for (GridSpan::iterator trackPosition = span.begin(); trackPosition != span.end(); ++trackPosition)
-        gridAreaBreadth += tracks[trackPosition.toInt()].baseSize();
+    for (const auto& trackPosition : span)
+        gridAreaBreadth += tracks[trackPosition].baseSize();
 
     gridAreaBreadth += guttersSize(direction, span.integerSpan());
 
     return gridAreaBreadth;
 }
 
 LayoutUnit LayoutGrid::gridAreaBreadthForChildIncludingAlignmentOffsets(const LayoutBox& child, GridTrackSizingDirection direction, const GridSizingData& sizingData) const
 {
     // We need the cached value when available because Content Distribution alignment properties
     // may have some influence in the final grid area breadth.
     const Vector<GridTrack>& tracks = (direction == ForColumns) ? sizingData.columnTracks : sizingData.rowTracks;
     const GridSpan& span = cachedGridSpan(child, direction);
     const Vector<LayoutUnit>& linePositions = (direction == ForColumns) ? m_columnPositions : m_rowPositions;
-    LayoutUnit initialTrackPosition = linePositions[span.resolvedInitialPosition().toInt()];
-    LayoutUnit finalTrackPosition = linePositions[span.resolvedFinalPosition().prev().toInt()];
+    LayoutUnit initialTrackPosition = linePositions[span.resolvedInitialPosition()];
+    LayoutUnit finalTrackPosition = linePositions[span.resolvedFinalPosition() - 1];
     // Track Positions vector stores the 'start' grid line of each track, so w have to add last track's baseSize.
-    return finalTrackPosition - initialTrackPosition + tracks[span.resolvedFinalPosition().prev().toInt()].baseSize();
+    return finalTrackPosition - initialTrackPosition + tracks[span.resolvedFinalPosition() - 1].baseSize();
 }
 
 void LayoutGrid::populateGridPositions(GridSizingData& sizingData)
 {
     // Since we add alignment offsets and track gutters, grid lines are not always adjacent. Hence we will have to
     // assume from now on that we just store positions of the initial grid lines of each track,
     // except the last one, which is the only one considered as a final grid line of a track.
     // FIXME: This will affect the computed style value of grid tracks size, since we are
     // using these positions to compute them.
 
@@ skipping 286 matching lines @@
 
 static inline LayoutUnit offsetBetweenTracks(ContentDistributionType distribution, const Vector<LayoutUnit>& trackPositions, const LayoutUnit& childBreadth)
 {
     return (distribution == ContentDistributionStretch || ContentDistributionStretch == ContentDistributionDefault) ? LayoutUnit() : trackPositions[1] - trackPositions[0] - childBreadth;
 
 }
 
 LayoutUnit LayoutGrid::columnAxisOffsetForChild(const LayoutBox& child) const
 {
     const GridSpan& rowsSpan = cachedGridSpan(child, ForRows);
-    size_t childStartLine = rowsSpan.resolvedInitialPosition().toInt();
+    size_t childStartLine = rowsSpan.resolvedInitialPosition();
     LayoutUnit startOfRow = m_rowPositions[childStartLine];
     LayoutUnit startPosition = startOfRow + marginBeforeForChild(child);
     if (hasAutoMarginsInColumnAxis(child))
         return startPosition;
     GridAxisPosition axisPosition = columnAxisPositionForChild(child);
     switch (axisPosition) {
     case GridAxisStart:
         return startPosition;
     case GridAxisEnd:
     case GridAxisCenter: {
-        size_t childEndLine = rowsSpan.resolvedFinalPosition().toInt();
+        size_t childEndLine = rowsSpan.resolvedFinalPosition();
         LayoutUnit endOfRow = m_rowPositions[childEndLine];
         // m_rowPositions include gutters so we need to substract them to get the actual end position for a given
         // row (this does not have to be done for the last track as there are no more m_rowPositions after it)
         if (childEndLine < m_rowPositions.size() - 1)
             endOfRow -= guttersSize(ForRows, 2);
         LayoutUnit childBreadth = child.logicalHeight() + child.marginLogicalHeight();
         if (childEndLine - childStartLine > 1 && childEndLine < m_rowPositions.size() - 1)
             endOfRow -= offsetBetweenTracks(styleRef().alignContentDistribution(), m_rowPositions, childBreadth);
         LayoutUnit offsetFromStartPosition = computeOverflowAlignmentOffset(child.styleRef().alignSelfOverflowAlignment(), endOfRow - startOfRow, childBreadth);
         return startPosition + (axisPosition == GridAxisEnd ? offsetFromStartPosition : offsetFromStartPosition / 2);
     }
     }
 
     ASSERT_NOT_REACHED();
     return 0;
 }
 
 LayoutUnit LayoutGrid::rowAxisOffsetForChild(const LayoutBox& child) const
 {
     const GridSpan& columnsSpan = cachedGridSpan(child, ForColumns);
-    size_t childStartLine = columnsSpan.resolvedInitialPosition().toInt();
+    size_t childStartLine = columnsSpan.resolvedInitialPosition();
     LayoutUnit startOfColumn = m_columnPositions[childStartLine];
     LayoutUnit startPosition = startOfColumn + marginStartForChild(child);
     if (hasAutoMarginsInRowAxis(child))
         return startPosition;
     GridAxisPosition axisPosition = rowAxisPositionForChild(child);
     switch (axisPosition) {
     case GridAxisStart:
         return startPosition;
     case GridAxisEnd:
     case GridAxisCenter: {
-        size_t childEndLine = columnsSpan.resolvedFinalPosition().toInt();
+        size_t childEndLine = columnsSpan.resolvedFinalPosition();
         LayoutUnit endOfColumn = m_columnPositions[childEndLine];
         // m_columnPositions include gutters so we need to substract them to get the actual end position for a given
         // column (this does not have to be done for the last track as there are no more m_columnPositions after it)
         if (childEndLine < m_columnPositions.size() - 1)
             endOfColumn -= guttersSize(ForRows, 2);
         LayoutUnit childBreadth = child.logicalWidth() + child.marginLogicalWidth();
         if (childEndLine - childStartLine > 1 && childEndLine < m_columnPositions.size() - 1)
             endOfColumn -= offsetBetweenTracks(styleRef().justifyContentDistribution(), m_columnPositions, childBreadth);
         LayoutUnit offsetFromStartPosition = computeOverflowAlignmentOffset(child.styleRef().justifySelfOverflowAlignment(), endOfColumn - startOfColumn, childBreadth);
         return startPosition + (axisPosition == GridAxisEnd ? offsetFromStartPosition : offsetFromStartPosition / 2);
@@ skipping 130 matching lines @@
 
     return LayoutPoint(rowAxisOffset, columnAxisOffsetForChild(child));
 }
 
 void LayoutGrid::paintChildren(const PaintInfo& paintInfo, const LayoutPoint& paintOffset) const
 {
     GridPainter(*this).paintChildren(paintInfo, paintOffset);
 }
 
 } // namespace blink