Link Swarming Tasklist and Botlist together

appengine/swarming/ui/res/imp/botpage/bot-page.html

 <!--
   Copyright 2016 The LUCI Authors. All rights reserved.
   Use of this source code is governed under the Apache License, Version 2.0
   that can be found in the LICENSE file.
 
   This in an HTML Import-able file that contains the definition
   of the following elements:
 
     <bot-page>
 
@@ skipping 177 matching lines @@
                       href$="[[_taskLink(_bot.task_id)]]">
                     [[_task(_bot)]]
                   </a>
                 </td>
                 <td>
                 <!-- TODO(kjlubick) add the cancel button when swarming can
                 cancel running tasks -->
                 </td>
               </tr>
               <tr>
-                <td rowspan$="[[_numRows(_bot.dimensions)]]">Dimensions</td>
+                <td rowspan$="[[_numRows(_bot.dimensions)]]">
+                  <a href$="[[_siblingBotsLink(_bot.dimensions)]]" title="The list of bots that also matches these dimensions (except id)."> Dimensions</a>
+                </td>
               </tr>
               <template
                   is="dom-repeat"
                   items="[[_bot.dimensions]]"
                   as="dim">
                 <tr>
                   <td>[[dim.key]]</td>
                   <td>[[_concat(dim.value)]]</td>
                 </tr>
               </template>
@@ skipping 375 matching lines @@
           return "";
         }
         return str.substring(0, length);
       },
 
       _shutdownBot: function() {
         swarming.postWithToast("/api/swarming/v1/bot/"+this.bot_id+"/terminate",
           "Shutting down "+this.bot_id, this._auth_headers);
       },
 
+      _siblingBotsLink(dimensions) {
+        var cols = ["id", "os", "task", "status"];
+         if (!dimensions) {
+          return this._botListLink([], cols);
+        }
+
+        dimensions = dimensions.filter(function(f){
+          return f.key !== "id";
+        });
+
+        dimensions.forEach(function(f) {
+          if (cols.indexOf(f.key) === -1) {
+            cols.push(f.key);
+          }
+        }.bind(this));
+
+        return this._botListLink(dimensions, cols);
+      },
+
       _task: function(bot) {
         return (bot && bot.task_id) || "idle";
       },
 
       _taskClass: function(task) {
         if (task && task.internal_failure) {
           return "bot_died";
         }
         if (task && task.failure) {
           return "failed_task";
         }
         return "";
       },
 
       _toggleState: function() {
         this.set("_show_state", !this._show_state);
       }
 
     });
   })();
   </script>
 </dom-module>