(stable) Make dashboard arrange actions (move, add, remove) work again after read locking from "chaos reduction"

Summary:
See PHI385. Ref T13054. Ref T13083. The dashboard "arrange" operations (add, remove, move) rely on doing `$dashboard->setThing(...)` and then applying transactions.

This no longer works after the read locking change from T13054. To make this function again, just add an explicit `save()` after layout adjustment. This should be more nuanced eventually, but all arrange operations are nonfunctional in a corrupting way at HEAD of `master`/`stable`, so stop the bleeding first.

Test Plan:
  - Created new empty and template dashboards.
  - Moved panels.
  - Added new and existing panels.
  - Removed panels.

Maniphest Tasks: T13083, T13054

Differential Revision: https://secure.phabricator.com/D19123

src/applications/dashboard/storage/PhabricatorDashboard.php

@@ -74,7 +74,15 @@ final class PhabricatorDashboard extends PhabricatorDashboardDAO
 
   public function setLayoutConfigFromObject(
     PhabricatorDashboardLayoutConfig $object) {
+
     $this->setLayoutConfig($object->toDictionary());
+
+    // See PHI385. Dashboard panel mutations rely on changes to the Dashboard
+    // object persisting when transactions are applied, but this assumption is
+    // no longer valid after T13054. For now, just save the dashboard
+    // explicitly.
+    $this->save();
+
     return $this;
   }
 

src/applications/dashboard/typeahead/PhabricatorDashboardPanelDatasource.php

@@ -34,8 +34,10 @@ final class PhabricatorDashboardPanelDatasource
       $impl = $panel->getImplementation();
       if ($impl) {
         $type_text = $impl->getPanelTypeName();
+        $icon = $impl->getIcon();
       } else {
         $type_text = nonempty($panel->getPanelType(), pht('Unknown Type'));
+        $icon = 'fa-question';
       }
       $id = $panel->getID();
       $monogram = $panel->getMonogram();
@@ -44,7 +46,7 @@ final class PhabricatorDashboardPanelDatasource
       $result = id(new PhabricatorTypeaheadResult())
         ->setName($monogram.' '.$panel->getName())
         ->setPHID($id)
-        ->setIcon($impl->getIcon())
+        ->setIcon($icon)
         ->addAttribute($type_text);
 
       if (!empty($properties['class'])) {