Convert some phutil_escape_html() to hsprintf()

Summary: Found by `sgrep_php -e '"...".phutil_escape_html(...)'`.

Test Plan:
/
/D1
/uiexample/
/countdown/1/
/herald/transcript/1/all/

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T2432

Differential Revision: https://secure.phabricator.com/D4869

src/applications/differential/controller/DifferentialCommentSaveController.php

@@ -56,7 +56,7 @@ final class DifferentialCommentSaveController extends DifferentialController {
 
       $dialog->setTitle(pht('Action Has No Effect'));
       $dialog->appendChild(
-        '<p>'.phutil_escape_html($no_effect->getMessage()).'</p>');
+        phutil_tag('p', array(), $no_effect->getMessage()));
 
       if (strlen($comment) || $has_inlines) {
         $dialog->addSubmitButton(pht('Post as Comment'));