Several small changes to new UI pages

appengine/swarming/elements/res/imp/tasklist/task-list.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:
 
     <task-list>
 
@@ skipping 118 matching lines @@
               </th>
 
               <th hidden$="[[_hide('deduped_from', _columns.*)]]">
                 <span>Deduped from</span>
                 <sort-toggle
                     name="deduped_from"
                     current="[[_sort]]">
                 </sort-toggle>
               </th>
 
+              <th hidden$="[[_hide('sk_revision', _columns.*)]]">
+                <span>Skia Revision</span>
+                <sort-toggle
+                    name="sk_revision"
+                    current="[[_sort]]">
+                </sort-toggle>
+              </th>
+
               <template
                     is="dom-repeat"
                     items="[[_plainColumns]]"
                     as="c">
                 <th hidden$="[[_hide(c)]]">
                   <span>[[_header(c)]]</span>
                   <sort-toggle
                       name="[[c]]"
                       current="[[_sort]]">
                   </sort-toggle>
@@ skipping 37 matching lines @@
                 </td>
                 <td hidden$="[[_hide('deduped_from', _columns.*)]]">
                   <a
                       class="center"
                       href$="[[_taskLink(task.deduped_from)]]"
                       target="_blank">
                       [[_column('deduped_from',task)]]
                   </a>
                 </td>
 
+                <td hidden$="[[_hide('sk_revision', _columns.*)]]">
+                  <a
+                      class="center"
+                      href$="[[_skLink(task)]]"
+                      target="_blank">
+                      [[_column('sk_revision',task)]]
+                  </a>
+                </td>
+
                 <template
                     is="dom-repeat"
                     items="[[_plainColumns]]"
                     as="c">
                   <td hidden$="[[_hide(c)]]">
                     [[_column(c, task)]]
                   </td>
                 </template>
 
               </tr>
@@ skipping 40 matching lines @@
       bot: function(task) {
         return this._attribute(task, "bot_id")[0];
       },
       completed_ts: humanTime("completed_ts"),
       costs_usd: function(task) {
         return this._attribute(task, "costs_usd", 0)[0];
       },
       created_ts: humanTime("created_ts"),
       duration: humanTime("duration"),
       modified_ts: humanTime("modified_ts"),
+      sk_revision: function(task) {
+        var r = this._attribute(task, "sk_revision")[0];
+        return r.substring(0,8);
+      },
       started_ts: humanTime("started_ts"),
       state: function(task) {
         var state = this._attribute(task, "state")[0];
         if (state === "COMPLETED") {
 
           if (this._attribute(task, "failure", false)[0]) {
             return "COMPLETED (FAILURE)";
           }
           var tryNum = this._attribute(task, "try_number", "-1")[0];
           if (tryNum === "0") {
@@ skipping 128 matching lines @@
       },
 
       reload: function() {
         if (!this._auth_headers || !this._query_params) {
           return;
         }
         var url = "/_ah/api/swarming/v1/tasks/list?" + sk.query.fromParamSet(this._query_params);
         this.$.page_tasks.load(url,this._auth_headers);
       },
 
+      _skLink: function(task) {
+        var r = this._attribute(task, "sk_revision")[0];
+        if (r === "none") {
+          return undefined;

[stephana, 2016/10/03 19:58:35]

who not return empty string ? 

[kjlubick, 2016/10/03 20:07:45]

Empty string is a valid "href" and so the links are clickable even though they
go nowhere.  However, false seems to do what I want, so I made it return that
instead.

[stephana, 2016/10/04 13:24:32]

Acknowledged.

+        }
+        return "https://skia.googlesource.com/skia/+/" + r;
+      },
+
       _tag: function(task, col) {
         if (!task || !task.tagMap) {
           return undefined;
         }
         return task.tagMap[col];
       },
 
       _taskClass: function(task) {
         return this.stateClass(this._column("state", task));
       }
     });
   })();
   </script>
 </dom-module>