RenderGrid should include grid items' margins in its intrinsic size

LayoutTests/fast/css-grid-layout/grid-preferred-logical-widths.html

Index: LayoutTests/fast/css-grid-layout/grid-preferred-logical-widths.html
diff --git a/LayoutTests/fast/css-grid-layout/grid-preferred-logical-widths.html b/LayoutTests/fast/css-grid-layout/grid-preferred-logical-widths.html
index 7e87ba5dc0c4985c292e443487c2f4e7fe9be38e..fb70e1c52f022895529eedde18de0d5dd793744d 100755
--- a/LayoutTests/fast/css-grid-layout/grid-preferred-logical-widths.html
+++ b/LayoutTests/fast/css-grid-layout/grid-preferred-logical-widths.html
@@ -36,6 +36,10 @@
     grid-definition-rows: 10px;
     font: 10px/1 Ahem;
 }
+
+.margins {
+    margin: 10px 20px 30px 40px;
+}
 </style>
 </head>
 <script src="../../resources/check-layout.js"></script>
@@ -77,5 +81,31 @@
     <div class="firstRowSecondColumn">XX XX XX</div>
 </div>
 
+<!-- Now with margin on one of the grid items. -->
+<div class="grid gridMinContentFixed min-content" data-expected-height="10" data-expected-width="100">
+    <div class="firstRowFirstColumn">XX XX XX</div>
+    <div class="firstRowSecondColumn margins">XX XX XX</div>
+</div>
+<div class="grid gridMinContentFixed max-content" data-expected-height="10" data-expected-width="120">
+    <div class="firstRowFirstColumn margins">XX XX XX</div>
+    <div class="firstRowSecondColumn">XX XX XX</div>
+</div>
+<div class="grid gridFixedMinContent min-content" data-expected-height="10" data-expected-width="60">
+    <div class="firstRowFirstColumn">XXXXX XXXXX</div>
+    <div class="firstRowSecondColumn margins">XXXXX XXXXX</div>
+</div>
+<div class="grid gridFixedMinContent max-content" data-expected-height="10" data-expected-width="160">
+    <div class="firstRowFirstColumn margins">XXXXX XXXXX</div>
+    <div class="firstRowSecondColumn">XXXXX XXXXX</div>
+</div>
+<div class="grid gridFixedMaxContent min-content" data-expected-height="10" data-expected-width="80">
+    <div class="firstRowFirstColumn">XX XX XX</div>
+    <div class="firstRowSecondColumn margins">XX XX XX</div>
+</div>
+<div class="grid gridFixedMaxContent max-content" data-expected-height="10" data-expected-width="220">
+    <div class="firstRowFirstColumn margins">XX XX XX</div>
+    <div class="firstRowSecondColumn">XX XX XX</div>
+</div>
+
 </body>
 </html>