[Sheriff-o-matic] Use before content hax to hide category labels instead of ever-present spans

Tools/GardeningServer/ui/ct-unexpected-failures.html

Index: Tools/GardeningServer/ui/ct-unexpected-failures.html
diff --git a/Tools/GardeningServer/ui/ct-unexpected-failures.html b/Tools/GardeningServer/ui/ct-unexpected-failures.html
index bf2773799df78ef209e7fde0f9b87fea19a00432..0f06bc0e5ae334f220727fa4b0bb416ddc01fffb 100644
--- a/Tools/GardeningServer/ui/ct-unexpected-failures.html
+++ b/Tools/GardeningServer/ui/ct-unexpected-failures.html
@@ -46,11 +46,9 @@ found in the LICENSE file.
     <ct-tree-status status="{{ treeStatuses['chromium'] }}" state="{{ treeStatuses['chromium'].status }}"></ct-tree-status>
     <ct-tree-status status="{{ treeStatuses['blink'] }}" state="{{ treeStatuses['blink'].status }}"></ct-tree-status>
     <ct-party-time failures="{{ failures.failures[tree].length == 0 }}"></ct-party-time>
-    <ct-failure-stream category="default" groups="{{ failures.failures[tree] }}" commitLog="{{ commitLog }}" tree="{{ tree }}"></ct-failure-stream>
-    <span class="failure-group-header">Failures that have only happened once (on one bot):</span>
-    <ct-failure-stream category="failedOnce" groups="{{ failures.failures[tree] }}" commitLog="{{ commitLog }}" tree="{{ tree }}"></ct-failure-stream>
-    <span class="failure-group-header">Snoozed failures:</span>
-    <ct-failure-stream category="snoozed" groups="{{ failures.failures[tree] }}" commitLog="{{ commitLog }}" tree="{{ tree }}"></ct-failure-stream>
+    <ct-failure-stream title="Reliable failures" category="default" groups="{{ failures.failures[tree] }}" commitLog="{{ commitLog }}" tree="{{ tree }}"></ct-failure-stream>
+    <ct-failure-stream title="Failures that have only happened once (on one bot)" category="failedOnce" groups="{{ failures.failures[tree] }}" commitLog="{{ commitLog }}" tree="{{ tree }}"></ct-failure-stream>
+    <ct-failure-stream title="Snoozed failures" category="snoozed" groups="{{ failures.failures[tree] }}" commitLog="{{ commitLog }}" tree="{{ tree }}"></ct-failure-stream>
   </template>
   <script>
   (function() {