Allow %f2 and other escape sequences in editor link

Test Plan: Open in Editor.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran

Differential Revision: https://secure.phabricator.com/D2184

src/applications/people/controller/settings/panels/preferences/PhabricatorUserPreferenceSettingsPanelController.php

@@ -81,7 +81,7 @@ EXAMPLE;
         ->setCaption(
           'Link to edit files in external editor. '.
           '%f is replaced by filename, %l by line number, %r by repository '.
-          'callsign. '.
+          'callsign, %% by literal %. '.
           "For documentation, see {$editor_doc_link}.")
         ->setValue($preferences->getPreference($pref_editor)))
       ->appendChild(

src/applications/people/storage/user/PhabricatorUser.php

@@ -418,6 +418,7 @@ final class PhabricatorUser extends PhabricatorUserDAO {
       PhabricatorUserPreferences::PREFERENCE_EDITOR);
     if ($editor) {
       return strtr($editor, array(
+        '%%' => '%',
         '%f' => phutil_escape_uri($path),
         '%l' => phutil_escape_uri($line),
         '%r' => phutil_escape_uri($callsign),