Add UI to mass delete dead bots

appengine/swarming/ui/res/imp/botlist/bot-filters.html

Index: appengine/swarming/ui/res/imp/botlist/bot-filters.html
diff --git a/appengine/swarming/ui/res/imp/botlist/bot-filters.html b/appengine/swarming/ui/res/imp/botlist/bot-filters.html
index 82028d427cf8c09805faf4c12d3e7655f3137ac2..32552ac7be82276fbaa307df6324280019f923a8 100644
--- a/appengine/swarming/ui/res/imp/botlist/bot-filters.html
+++ b/appengine/swarming/ui/res/imp/botlist/bot-filters.html
@@ -47,13 +47,21 @@
     None.
 
   Events:
-    None.
+  The events this element fires are to work around the fact that modal paper-dialog
+  elements need to be outside all other elements on the DOM.
+
+    delete-all: The user wishes to delete all dead bots. The parent is expected
+        to show a paper-dialog and confirm the details.  The event's details
+        is {dimensions: {Array:String}} of the dimensions of bots that need be
+        deleted. It is expected that the parent will add the &is_dead=TRUE to
+        the request.
 -->
 
 <link rel="import" href="/res/imp/bower_components/iron-a11y-keys/iron-a11y-keys.html">
 <link rel="import" href="/res/imp/bower_components/iron-flex-layout/iron-flex-layout-classes.html">
 <link rel="import" href="/res/imp/bower_components/iron-icons/iron-icons.html">
 <link rel="import" href="/res/imp/bower_components/iron-selector/iron-selector.html">
+<link rel="import" href="/res/imp/bower_components/paper-button/paper-button.html">
 <link rel="import" href="/res/imp/bower_components/paper-checkbox/paper-checkbox.html">
 <link rel="import" href="/res/imp/bower_components/paper-icon-button/paper-icon-button.html">
 <link rel="import" href="/res/imp/bower_components/paper-input/paper-input.html">
@@ -67,7 +75,10 @@
 <dom-module id="bot-filters">
   <template>
     <style is="custom-style" include="iron-flex iron-flex-alignment iron-positioning query-column-filter-style swarming-app-style">
-
+    .delete-button {
+      display: block;
+      margin-top: 5px;
+    }
     </style>
 
     <url-param name="f"
@@ -183,6 +194,11 @@ the fleet.">
             value="{{_limit}}">
           </paper-input>
           <a href$="[[_matchingTasksLink(query_params)]]">View Matching Tasks</a>
+          <template is="dom-if" if="[[permissions.delete_bot]]">
+            <paper-button class="delete-button" raised on-tap="_promptDelete">
+              Delete All Dead bots
+            </paper-button>
+          </template>
         </div>
       </div>
 
@@ -241,6 +257,9 @@ the fleet.">
           type: Array,
           notify: true,
         },
+        permissions: {
+          type: Object,
+        },
         query_params: {
           type: Object,
           computed: "_extractQueryParams(dimensions.*,_filters.*, _limit)",
@@ -337,6 +356,14 @@ the fleet.">
         return this._taskListLink(query_params.dimensions, cols);
       },
 
+      _promptDelete: function() {
+        if (!this.query_params.dimensions || !this.query_params.dimensions.length) {
+          sk.errorMessage("You must specify at least one dimension to filter by first.", 8000);
+          return;
+        }
+        this.fire("delete-all",{dimensions:this.query_params.dimensions});
+      },
+
       _showDimensionMessage: function(primarySelected, selectedItems) {
         return primarySelected && primarySelected !== "id" && !selectedItems;
       }