[css-grid] Refactor intrinsic size computation code

The code which computes the intrinsic logical width of the grid container
and the rows sizes with indefinite height is exactly the same but operating
in different axis. Refactored so that we don't have to write the
initialization and tear down code twice.

Review-Url: https://codereview.chromium.org/2347613003
Cr-Commit-Position: refs/heads/master@{#419158}

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

@@ -405,7 +405,7 @@ LayoutUnit LayoutGrid::computeTrackBasedLogicalHeight(const GridSizingData& sizi
     return logicalHeight;
 }
 
-void LayoutGrid::computeTrackSizesForDirection(GridTrackSizingDirection direction, GridSizingData& sizingData, LayoutUnit availableSpace)
+void LayoutGrid::computeTrackSizesForDefiniteSize(GridTrackSizingDirection direction, GridSizingData& sizingData, LayoutUnit availableSpace) const
 {
     DCHECK(sizingData.isValidTransition(direction));
     sizingData.setAvailableSpace(availableSpace);
@@ -431,8 +431,8 @@ void LayoutGrid::repeatTracksSizingIfNeeded(GridSizingData& sizingData, LayoutUn
     // cases with orthogonal flows require this extra cycle; we need a more specific
     // condition to detect whether child's min-content contribution has changed or not.
     if (m_hasAnyOrthogonalChild) {
-        computeTrackSizesForDirection(ForColumns, sizingData, availableSpaceForColumns);
-        computeTrackSizesForDirection(ForRows, sizingData, availableSpaceForRows);
+        computeTrackSizesForDefiniteSize(ForColumns, sizingData, availableSpaceForColumns);
+        computeTrackSizesForDefiniteSize(ForRows, sizingData, availableSpaceForRows);
     }
 }
 
@@ -471,14 +471,17 @@ void LayoutGrid::layoutBlock(bool relayoutChildren)
         // paths inside updateLogicalHeight() require a previous call to setLogicalHeight() to resolve
         // heights properly (like for positioned items for example).
         LayoutUnit availableSpaceForColumns = availableLogicalWidth();
-        computeTrackSizesForDirection(ForColumns, sizingData, availableSpaceForColumns);
+        computeTrackSizesForDefiniteSize(ForColumns, sizingData, availableSpaceForColumns);
 
         // 2- Next, the track sizing algorithm resolves the sizes of the grid rows, using the
         // grid column sizes calculated in the previous step.
-        if (cachedHasDefiniteLogicalHeight())
-            computeTrackSizesForDirection(ForRows, sizingData, availableLogicalHeight(ExcludeMarginBorderPadding));
-        else
-            computeIntrinsicLogicalHeight(sizingData);
+        if (cachedHasDefiniteLogicalHeight()) {
+            computeTrackSizesForDefiniteSize(ForRows, sizingData, availableLogicalHeight(ExcludeMarginBorderPadding));
+        } else {
+            computeTrackSizesForIndefiniteSize(ForRows, sizingData, m_minContentHeight, m_maxContentHeight);
+            sizingData.nextState();
+            sizingData.sizingOperation = TrackSizing;
+        }
         setLogicalHeight(computeTrackBasedLogicalHeight(sizingData) + borderAndPaddingLogicalHeight() + scrollbarLogicalHeight());
 
         LayoutUnit oldClientAfterEdge = clientLogicalBottom();
@@ -601,36 +604,30 @@ void LayoutGrid::computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, Layo
     const_cast<LayoutGrid*>(this)->placeItemsOnGrid(IntrinsicSizeComputation);
 
     GridSizingData sizingData(gridColumnCount(), gridRowCount());
-    sizingData.setAvailableSpace(LayoutUnit());
-    sizingData.freeSpace(ForColumns) = LayoutUnit();
-    sizingData.sizingOperation = IntrinsicSizeComputation;
-    computeUsedBreadthOfGridTracks(ForColumns, sizingData, minLogicalWidth, maxLogicalWidth);
-
-    LayoutUnit totalGuttersSize = guttersSize(ForColumns, 0, sizingData.columnTracks.size(), sizingData.sizingOperation);
-    minLogicalWidth += totalGuttersSize;
-    maxLogicalWidth += totalGuttersSize;
+    computeTrackSizesForIndefiniteSize(ForColumns, sizingData, minLogicalWidth, maxLogicalWidth);
 
     LayoutUnit scrollbarWidth = LayoutUnit(scrollbarLogicalWidth());
     minLogicalWidth += scrollbarWidth;
     maxLogicalWidth += scrollbarWidth;
 }
 
-void LayoutGrid::computeIntrinsicLogicalHeight(GridSizingData& sizingData)
+void LayoutGrid::computeTrackSizesForIndefiniteSize(GridTrackSizingDirection direction, GridSizingData& sizingData, LayoutUnit& minIntrinsicSize, LayoutUnit& maxIntrinsicSize) const
 {
-    DCHECK(sizingData.isValidTransition(ForRows));
-    ASSERT(tracksAreWiderThanMinTrackBreadth(ForColumns, sizingData));
+    DCHECK(sizingData.isValidTransition(direction));
     sizingData.setAvailableSpace(LayoutUnit());
-    sizingData.freeSpace(ForRows) = LayoutUnit();
+    sizingData.freeSpace(direction) = LayoutUnit();
     sizingData.sizingOperation = IntrinsicSizeComputation;
-    computeUsedBreadthOfGridTracks(ForRows, sizingData, m_minContentHeight, m_maxContentHeight);
 
-    LayoutUnit totalGuttersSize = guttersSize(ForRows, 0, gridRowCount(), sizingData.sizingOperation);
-    m_minContentHeight += totalGuttersSize;
-    m_maxContentHeight += totalGuttersSize;
+    computeUsedBreadthOfGridTracks(direction, sizingData, minIntrinsicSize, maxIntrinsicSize);
 
-    ASSERT(tracksAreWiderThanMinTrackBreadth(ForRows, sizingData));
-    sizingData.nextState();
-    sizingData.sizingOperation = TrackSizing;
+    size_t numberOfTracks = direction == ForColumns ? sizingData.columnTracks.size() : sizingData.rowTracks.size();
+    LayoutUnit totalGuttersSize = guttersSize(direction, 0, numberOfTracks, sizingData.sizingOperation);
+    minIntrinsicSize += totalGuttersSize;
+    maxIntrinsicSize += totalGuttersSize;
+
+#if ENABLE(ASSERT)
+    DCHECK(tracksAreWiderThanMinTrackBreadth(direction, sizingData));
+#endif
 }
 
 LayoutUnit LayoutGrid::computeIntrinsicLogicalContentHeightUsing(const Length& logicalHeightLength, LayoutUnit intrinsicContentHeight, LayoutUnit borderAndPadding) const
@@ -1404,7 +1401,7 @@ void LayoutGrid::distributeSpaceToTracks(Vector<GridTrack*>& tracks, Vector<Grid
 }
 
 #if ENABLE(ASSERT)
-bool LayoutGrid::tracksAreWiderThanMinTrackBreadth(GridTrackSizingDirection direction, GridSizingData& sizingData)
+bool LayoutGrid::tracksAreWiderThanMinTrackBreadth(GridTrackSizingDirection direction, GridSizingData& sizingData) const
 {
     const Vector<GridTrack>& tracks = (direction == ForColumns) ? sizingData.columnTracks : sizingData.rowTracks;
     LayoutUnit& maxSize = sizingData.freeSpace(direction);

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

@@ -142,9 +142,9 @@ private:
     GridTrackSizingDirection autoPlacementMajorAxisDirection() const;
     GridTrackSizingDirection autoPlacementMinorAxisDirection() const;
 
-    void computeIntrinsicLogicalHeight(GridSizingData&);
+    void computeTrackSizesForIndefiniteSize(GridTrackSizingDirection, GridSizingData&, LayoutUnit& minIntrinsicSize, LayoutUnit& maxIntrinsicSize) const;
     LayoutUnit computeTrackBasedLogicalHeight(const GridSizingData&) const;
-    void computeTrackSizesForDirection(GridTrackSizingDirection, GridSizingData&, LayoutUnit freeSpace);
+    void computeTrackSizesForDefiniteSize(GridTrackSizingDirection, GridSizingData&, LayoutUnit freeSpace) const;
 
     void repeatTracksSizingIfNeeded(GridSizingData&, LayoutUnit availableSpaceForColumns, LayoutUnit availableSpaceForRows);
 
@@ -205,7 +205,7 @@ private:
     void updateAutoMarginsInRowAxisIfNeeded(LayoutBox&);
 
 #if ENABLE(ASSERT)
-    bool tracksAreWiderThanMinTrackBreadth(GridTrackSizingDirection, GridSizingData&);
+    bool tracksAreWiderThanMinTrackBreadth(GridTrackSizingDirection, GridSizingData&) const;
 #endif
 
     LayoutUnit gridGapForDirection(GridTrackSizingDirection, SizingOperation) const;