Update our treatment of repeating headers in tables

third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-starts-middle-of-page-break-after-avoid-expected.html

Index: third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-starts-middle-of-page-break-after-avoid-expected.html
diff --git a/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-starts-middle-of-page-break-after-avoid-expected.html b/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-starts-middle-of-page-break-after-avoid-expected.html
index 54f5c2f1e307ba2c2041378d806a3ea1c0465bcf..6ae34d46a22bacd2ace91591af967391200f9600 100644
--- a/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-starts-middle-of-page-break-after-avoid-expected.html
+++ b/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-starts-middle-of-page-break-after-avoid-expected.html
@@ -10,6 +10,10 @@ td, th {
 tr {
     break-inside: avoid;
 }
+.header {
+    font-weight: bold;
+    text-align: center
+}
 </style>
 <p>crbug.com/624814: A table header group should not repeat on each page if we can't fit at least one content row below it.</p>
 <div style="-webkit-columns:3; line-height: 20px; column-fill: auto; height:190px; background-color: yellow;">
@@ -22,13 +26,9 @@ tr {
     <br>
     <br>
     <table>
-        <thead>
-            <tr>
-                <th>Col 1</th>
-                <th>Col 2</th>
-            </tr>
-        </thead>
+        <tr><td class="header">Col 1</td><td class="header">Col 2</td></tr>
         <tbody>
+        <tr><td class="header">Col 1</td><td class="header">Col 2</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
@@ -36,6 +36,7 @@ tr {
         <tr><td>Te</td><td>xt</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
+        <tr><td class="header">Col 1</td><td class="header">Col 2</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
@@ -43,6 +44,7 @@ tr {
         <tr><td>Te</td><td>xt</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
+        <tr><td class="header">Col 1</td><td class="header">Col 2</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
         <tr><td>Te</td><td>xt</td></tr>
         <tr><td>Te</td><td>xt</td></tr>