Add ability to delete timeline sheets

Note there is a bug that already exists in timeline where the
notify.info message disappears immediately.  Not fixing in this PR, but
the delete info message suffers the same bug as the save info message
does already.

src/core_plugins/timelion/public/app.js

@@ -46,7 +46,8 @@ require('ui/routes')
   });
 
 app.controller('timelion', function (
-  $scope, $http, timefilter, AppState, courier, $route, $routeParams, kbnUrl, Notifier, config, $timeout, Private, savedVisualizations) {
+    $scope, $http, timefilter, AppState, courier, $route, $routeParams,
+    kbnUrl, Notifier, config, $timeout, Private, savedVisualizations, safeConfirm) {
 
   // TODO: For some reason the Kibana core doesn't correctly do this for all apps.
   moment.tz.setDefault(config.get('dateFormat:tz'));
@@ -61,7 +62,6 @@ app.controller('timelion', function (
 
   var defaultExpression = '.es(*)';
   var savedSheet = $route.current.locals.savedSheet;
-  var blankSheet = [defaultExpression];
 
   $scope.topNavMenu = [{
     key: 'new',
@@ -78,6 +78,21 @@ app.controller('timelion', function (
     description: 'Save Sheet',
     template: require('plugins/timelion/partials/save_sheet.html'),
     testId: 'timelionSaveButton',
+  }, {
+    key: 'delete',
+    description: 'Delete current sheet',
+    disableButton: function () {
+      return !savedSheet.id;
+    },
+    run: function () {
+      var title = savedSheet.title;
+      safeConfirm('Are you sure you want to delete the sheet ' + title + ' ?').then(function () {
+        savedSheet.delete().then(() => {
+          notify.info('Deleted ' + title);
+          kbnUrl.change('/');
+        }).catch(notify.fatal);
+      });},
+    testId: 'timelionDeleteButton',
   }, {
     key: 'open',
     description: 'Open Sheet',
@@ -213,7 +228,6 @@ app.controller('timelion', function (
     savedSheet.timelion_columns = $scope.state.columns;
     savedSheet.timelion_rows = $scope.state.rows;
     savedSheet.save().then(function (id) {
-      //$scope.configTemplate.close('save');
       if (id) {
         notify.info('Saved sheet as "' + savedSheet.title + '"');
         if (savedSheet.id !== $routeParams.id) {