Expose the chromium waterfall in sheriff-o-matic.

Tools/GardeningServer/ui/ct-failure-stream.html

Index: Tools/GardeningServer/ui/ct-failure-stream.html
diff --git a/Tools/GardeningServer/ui/ct-failure-stream.html b/Tools/GardeningServer/ui/ct-failure-stream.html
index 3f15db5eaf74055b794418dd62f65276cc0ff8fa..66753342ffdd1f29ef6302422ab49036695afb1c 100644
--- a/Tools/GardeningServer/ui/ct-failure-stream.html
+++ b/Tools/GardeningServer/ui/ct-failure-stream.html
@@ -6,7 +6,7 @@ found in the LICENSE file.
 
 <link rel="import" href="ct-failure-card.html">
 
-<polymer-element name="ct-failure-stream" attributes="groups commits" noscript>
+<polymer-element name="ct-failure-stream" attributes="groups commits tree" noscript>
   <template>
     <style>
       :host {
@@ -20,7 +20,7 @@ found in the LICENSE file.
       }
     </style>
     <template repeat="{{failures in groups}}">
-      <ct-failure-card failures="{{failures}}" commits="{{commits}}"></ct-failure-card>
+      <ct-failure-card failures="{{ failures }}" commits="{{ commits }}" tree="{{ tree }}"></ct-failure-card>
     </template>
   </template>
 </polymer-element>