[CSS Grid Layout] Update grid-auto-flow to the new syntax

LayoutTests/fast/css-grid-layout/named-grid-lines-with-named-grid-areas-resolution.html

Index: LayoutTests/fast/css-grid-layout/named-grid-lines-with-named-grid-areas-resolution.html
diff --git a/LayoutTests/fast/css-grid-layout/named-grid-lines-with-named-grid-areas-resolution.html b/LayoutTests/fast/css-grid-layout/named-grid-lines-with-named-grid-areas-resolution.html
index 317bd37ca764a16cf7b069b58a8655469c9687b0..f36175d083fa6a08ed357ed58917d6d1fc5f8e9f 100644
--- a/LayoutTests/fast/css-grid-layout/named-grid-lines-with-named-grid-areas-resolution.html
+++ b/LayoutTests/fast/css-grid-layout/named-grid-lines-with-named-grid-areas-resolution.html
@@ -60,7 +60,7 @@
 
 <!-- Check positioning using unique grid-line names -->
 <div style="position: relative">
-  <div class="grid gridUniqueNames">
+  <div class="grid gridUniqueNames gridAutoFlowStack">
     <div class="sizedToGridArea" style="grid-column: b;" data-offset-x="50" data-offset-y="0" data-expected-width="100" data-expected-height="50"></div>
     <div class="sizedToGridArea" style="grid-row: e;" data-offset-x="0" data-offset-y="0" data-expected-width="50" data-expected-height="50"></div>
     <div class="sizedToGridArea" style="grid-column: b-start;" data-offset-x="50" data-offset-y="0" data-expected-width="100" data-expected-height="50"></div>
@@ -88,7 +88,7 @@
 
 <!-- Check that without named gridAreas there are no implicit grid-line names defined -->
 <div style="position: relative">
-  <div class="grid gridUniqueNames">
+  <div class="grid gridUniqueNames gridAutoFlowStack">
     <div class="sizedToGridArea" style="grid-column: c-start;" data-offset-x="0" data-offset-y="0" data-expected-width="50" data-expected-height="50"></div>
     <div class="sizedToGridArea" style="grid-row: f-start;" data-offset-x="0" data-offset-y="0" data-expected-width="50" data-expected-height="50"></div>
     <div class="sizedToGridArea" style="grid-column: c-start; grid-row: f-end" data-offset-x="0" data-offset-y="0" data-expected-width="50" data-expected-height="50"></div>
@@ -116,7 +116,7 @@
 </div>
 
 <div style="position: relative">
-  <div class="grid gridAreas gridNoLineNames">
+  <div class="grid gridAreas gridNoLineNames gridAutoFlowStack">
     <div class="sizedToGridArea" style="grid-column: a;" data-offset-x="50" data-offset-y="0" data-expected-width="300" data-expected-height="50"></div>
     <div class="sizedToGridArea" style="grid-row: a;" data-offset-x="0" data-offset-y="0" data-expected-width="50" data-expected-height="150"></div>
     <div class="sizedToGridArea" style="grid-column: a; grid-row: a;" data-offset-x="50" data-offset-y="0" data-expected-width="300" data-expected-height="150"></div>
@@ -150,7 +150,7 @@
 
 <!-- Use explicitly named grid lines if they're defined before the grid area -->
 <div style="position: relative">
-  <div class="grid gridAreas gridWithNamedLineBeforeGridArea">
+  <div class="grid gridAreas gridWithNamedLineBeforeGridArea gridAutoFlowStack">
     <div class="sizedToGridArea" style="grid-column: d;" data-offset-x="50" data-offset-y="0" data-expected-width="300" data-expected-height="50"></div>
     <div class="sizedToGridArea" style="grid-row: d;" data-offset-x="0" data-offset-y="50" data-expected-width="50" data-expected-height="300"></div>
     <div class="sizedToGridArea" style="grid-column: c;" data-offset-x="0" data-offset-y="0" data-expected-width="50" data-expected-height="50"></div>
@@ -166,7 +166,7 @@
 </div>
 
 <div style="position: relative">
-  <div class="grid gridAreas gridWithNamedLineBeforeGridArea">
+  <div class="grid gridAreas gridWithNamedLineBeforeGridArea gridAutoFlowStack">
     <div class="sizedToGridArea" style="grid-column: a;" data-offset-x="0" data-offset-y="0" data-expected-width="350" data-expected-height="50"></div>
     <div class="sizedToGridArea" style="grid-row: d;" data-offset-x="0" data-offset-y="50" data-expected-width="50" data-expected-height="300"></div>
     <div class="sizedToGridArea" style="grid-column: a; grid-row: d;" data-offset-x="0" data-offset-y="50" data-expected-width="350" data-expected-height="300"></div>
@@ -204,7 +204,7 @@
 
 <!-- Check behavior with areas named *-start or *-end -->
 <div style="position: relative">
-  <div class="grid gridAreasSpecial gridNoLineNames">
+  <div class="grid gridAreasSpecial gridNoLineNames gridAutoFlowStack">
     <div class="sizedToGridArea" style="grid-column: a;" data-offset-x="0" data-offset-y="0" data-expected-width="50" data-expected-height="50"></div>
     <div class="sizedToGridArea" style="grid-row: a;" data-offset-x="0" data-offset-y="0" data-expected-width="50" data-expected-height="50"></div>
     <div class="sizedToGridArea" style="grid-column: a; grid-row: a;" data-offset-x="0" data-offset-y="0" data-expected-width="50" data-expected-height="50"></div>