Conpherence - add draft support

Summary: Fixes T3497.

Test Plan: on conpherence 1, typed some stuff. clicked conpherence 2 - observed some stuff gone. clicked conpherence 1 - stuff came back! submitted conpherence 1 and reloaded - stuff did not come back.  (Generally played around a bunch like this)

Reviewers: epriestley

Reviewed By: epriestley

CC: Korvin, epriestley, aran

Maniphest Tasks: T3497

Differential Revision: https://secure.phabricator.com/D8266

src/applications/conpherence/controller/ConpherenceUpdateController.php

@@ -1,8 +1,5 @@
 <?php
 
-/**
- * @group conpherence
- */
 final class ConpherenceUpdateController
   extends ConpherenceController {
 
@@ -39,6 +36,7 @@ final class ConpherenceUpdateController
     $error_view = null;
     $e_file = array();
     $errors = array();
+    $delete_draft = false;
     if ($request->isFormPost()) {
       $editor = id(new ConpherenceEditor())
         ->setContinueOnNoEffect($request->isContinueRequest())
@@ -46,11 +44,19 @@ final class ConpherenceUpdateController
         ->setActor($user);
 
       switch ($action) {
+        case ConpherenceUpdateActions::DRAFT:
+          $draft = PhabricatorDraft::newFromUserAndKey(
+            $user,
+            $conpherence->getPHID());
+          $draft->setDraft($request->getStr('text'));
+          $draft->replaceOrDelete();
+          break;
         case ConpherenceUpdateActions::MESSAGE:
           $message = $request->getStr('text');
           $xactions = $editor->generateTransactionsFromText(
             $conpherence,
             $message);
+          $delete_draft = true;
           break;
         case ConpherenceUpdateActions::ADD_PERSON:
           $xactions = array();
@@ -116,6 +122,12 @@ final class ConpherenceUpdateController
       if ($xactions) {
         try {
           $xactions = $editor->applyTransactions($conpherence, $xactions);
+          if ($delete_draft) {
+            $draft = PhabricatorDraft::newFromUserAndKey(
+              $user,
+              $conpherence->getPHID());
+            $draft->delete();
+          }
         } catch (PhabricatorApplicationTransactionNoEffectException $ex) {
           return id(new PhabricatorApplicationTransactionNoEffectResponse())
             ->setCancelURI($this->getApplicationURI($conpherence_id.'/'))