[css-grid] Remove the 2x computation of row sizes w/ indefinite heights

On crrev.com/358816, among other things, we added a second pass of the track
sizing algorithm for rows in order to properly compute row sizes when the
height was indefinite. We did that in order to have a symmetrical
implementation for columns and rows, but unfortunatelly that was not
correct.

Apart from issuing incorrect results in some cases it created a huge
performance issue in the case of nested grids because we were exponentially
increasing the amount of executions of the track sizing algorithm. The attached
performance test shows a 350% improvement with the patch.

BUG=619629

Review-Url: https://codereview.chromium.org/2339983002
Cr-Commit-Position: refs/heads/master@{#418892}

third_party/WebKit/LayoutTests/fast/css-grid-layout/maximize-tracks-definite-indefinite-height.html

@@ -52,15 +52,15 @@
 </div>
 
 <div class="grid max-content max-height-35" data-expected-width="40" data-expected-height="35">
-    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="35">XX XXX XX XXX</div>
+    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX XXX XX XXX</div>
 </div>
 
 <div class="grid max-content max-height-min-content" data-expected-width="40" data-expected-height="0">
-    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="0">XX XXX X</div>
+    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX XXX X</div>
 </div>
 
 <div class="grid max-height-min-content" data-expected-width="40" data-expected-height="0">
-    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="0">XX XXX</div>
+    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX XXX</div>
 </div>
 
 <div class="grid max-content max-height-fill-available" data-expected-width="40" data-expected-height="100">
@@ -130,11 +130,11 @@
 </div>
 
 <div class="grid itemsStart min-content" data-expected-width="40" data-expected-height="0">
-    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="0">XX XX XX</div>
+    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX XX XX</div>
 </div>
 
 <div class="grid itemsStart min-content min-height-50" data-expected-width="40" data-expected-height="50">
-    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="50">XX X</div>
+    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX X</div>
 </div>
 
 <div class="grid itemsStart min-content min-height-fit-content" data-expected-width="40" data-expected-height="100">
@@ -148,11 +148,11 @@
 </div>
 
 <div class="grid itemsStart min-content min-height-min-content" data-expected-width="40" data-expected-height="0">
-    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="0">XX XXX</div>
+    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX XXX</div>
 </div>
 
 <div class="grid itemsStart min-content min-height-35" data-expected-width="40" data-expected-height="35">
-    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="35">XX XX</div>
+    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX XX</div>
 </div>
 
 <div class="grid itemsStart min-content min-height-max-content" data-expected-width="40" data-expected-height="100">
@@ -160,11 +160,11 @@
 </div>
 
 <div class="grid itemsStart min-content min-height-50" data-expected-width="40" data-expected-height="50">
-    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="50">XXXX XXXX XXXX XXXX</div>
+    <div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XXXX XXXX XXXX XXXX</div>
 </div>
 
 <div class="grid itemsStart min-content max-height-50" data-expected-width="40" data-expected-height="0">
-    <div class="sizedToGridArea min-height-fill-available" data-expected-width="40" data-expected-height="50">XXXX X X XXXX</div>
+    <div class="sizedToGridArea min-height-fill-available" data-expected-width="40" data-expected-height="100">XXXX X X XXXX</div>
 </div>
 
 <br>
@@ -207,7 +207,7 @@
 	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">X XXXX X</div>
     </div>
     <div class="grid itemsStart max-height-min-content" data-expected-width="40" data-expected-height="0">
-	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="0">XX XX XX</div>
+	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX XX XX</div>
     </div>
     <div class="grid itemsStart fit-content" data-expected-width="40" data-expected-height="100">
 	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">X XX X</div>
@@ -228,7 +228,7 @@
 	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XXXX X X</div>
     </div>
     <div class="grid itemsStart max-height-min-content" data-expected-width="40" data-expected-height="0">
-	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="0">X XXX XX</div>
+	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">X XXX XX</div>
     </div>
     <div class="grid itemsStart fit-content" data-expected-width="40" data-expected-height="100">
 	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX XXX XX X</div>
@@ -237,22 +237,22 @@
 
 <div class="fit-content min-height-50" style="height: 75px;">
     <div class="grid itemsStart fill-available" data-expected-width="40" data-expected-height="75">
-	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="75">XX X</div>
+	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX X</div>
     </div>
 </div>
 
 <div style="height: 25px;">
     <div class="grid itemsStart fit-content" data-expected-width="40" data-expected-height="25">
-	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="25">XX X</div>
+	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX X</div>
     </div>
     <div class="grid itemsStart fill-available" data-expected-width="40" data-expected-height="25">
-	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="25">XX X</div>
+	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX X</div>
     </div>
     <div class="grid itemsStart fit-content min-height-35" data-expected-width="40" data-expected-height="35">
-	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="35">XX X</div>
+	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX X</div>
     </div>
     <div class="grid itemsStart fit-content max-height-min-content" data-expected-width="40" data-expected-height="0">
-	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="0">XX X</div>
+	<div class="sizedToGridArea" data-expected-width="40" data-expected-height="100">XX X</div>
     </div>
 </div>
 

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

@@ -484,16 +484,10 @@ void LayoutGrid::layoutBlock(bool relayoutChildren)
         LayoutUnit oldClientAfterEdge = clientLogicalBottom();
         updateLogicalHeight();
 
-        // The above call might have changed the grid's logical height depending on min|max height restrictions.
-        // Update the sizes of the rows whose size depends on the logical height (also on definite|indefinite sizes).
-        LayoutUnit availableSpaceForRows = contentLogicalHeight();
-        if (!cachedHasDefiniteLogicalHeight())
-            computeTrackSizesForDirection(ForRows, sizingData, availableSpaceForRows);
-
         // 3- If the min-content contribution of any grid items have changed based on the row
         // sizes calculated in step 2, steps 1 and 2 are repeated with the new min-content
         // contribution (once only).
-        repeatTracksSizingIfNeeded(sizingData, availableSpaceForColumns, availableSpaceForRows);
+        repeatTracksSizingIfNeeded(sizingData, availableSpaceForColumns, contentLogicalHeight());
 
         // Grid container should have the minimum height of a line if it's editable. That doesn't affect track sizing though.
         if (hasLineIfEmpty())
@@ -623,6 +617,7 @@ void LayoutGrid::computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, Layo
 
 void LayoutGrid::computeIntrinsicLogicalHeight(GridSizingData& sizingData)
 {
+    DCHECK(sizingData.isValidTransition(ForRows));
     ASSERT(tracksAreWiderThanMinTrackBreadth(ForColumns, sizingData));
     sizingData.setAvailableSpace(LayoutUnit());
     sizingData.freeSpace(ForRows) = LayoutUnit();
@@ -634,6 +629,8 @@ void LayoutGrid::computeIntrinsicLogicalHeight(GridSizingData& sizingData)
     m_maxContentHeight += totalGuttersSize;
 
     ASSERT(tracksAreWiderThanMinTrackBreadth(ForRows, sizingData));
+    sizingData.nextState();
+    sizingData.sizingOperation = TrackSizing;
 }
 
 LayoutUnit LayoutGrid::computeIntrinsicLogicalContentHeightUsing(const Length& logicalHeightLength, LayoutUnit intrinsicContentHeight, LayoutUnit borderAndPadding) const
@@ -1892,6 +1889,7 @@ void LayoutGrid::applyStretchAlignmentToTracksIfNeeded(GridTrackSizingDirection
 
 void LayoutGrid::layoutGridItems(GridSizingData& sizingData)
 {
+    DCHECK_EQ(sizingData.sizingOperation, TrackSizing);
     populateGridPositionsForDirection(sizingData, ForColumns);
     populateGridPositionsForDirection(sizingData, ForRows);
     m_gridItemsOverflowingGridArea.resize(0);