Use "CommentPro" controller instead of "Comment" controller

Summary: Ref T2222. This will probabaly have a few rough edges too, but seems to work well.

Test Plan:
  - Made a bunch of comments while building this.
  - Made some new comments.
  - Verified that the Asana/JIRA integration is only a little bit janky, not completely broken.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T2222

Differential Revision: https://secure.phabricator.com/D8362

src/applications/differential/controller/DifferentialRevisionViewController.php

@@ -339,13 +339,8 @@ final class DifferentialRevisionViewController extends DifferentialController {
       // TODO: Restore the ability for fields to add accept warnings.
 
       $comment_form->setActions($this->getRevisionCommentActions($revision));
-
-      $action_uri = '/differential/comment/save/';
-      if (false) {
-        // TODO: Temporary for testing the new comment workflow.
-        $action_uri = $this->getApplicationURI(
-          'comment/savepro/'.$revision->getID().'/');
-      }
+      $action_uri = $this->getApplicationURI(
+        'comment/save/'.$revision->getID().'/');
 
       $comment_form->setActionURI($action_uri);
       $comment_form->setUser($user);