Use autosize in modals

Fixes #7338 and missing autosize in conversation forms on the profile page
and the contacts page. Regression from #6674.

closes #7339

Changelog.md

@@ -12,6 +12,7 @@
 * Update comment in database example config [#7282](https://github.com/diaspora/diaspora/pull/7282)
 * Make the \#newhere post public again [#7311](https://github.com/diaspora/diaspora/pull/7311)
 * Remove whitespace from author link [#7330](https://github.com/diaspora/diaspora/pull/7330)
+* Fix autosize in modals [#7339](https://github.com/diaspora/diaspora/pull/7339)
 
 ## Features
 * Add support for [Liberapay](https://liberapay.com) donations [#7290](https://github.com/diaspora/diaspora/pull/7290)

app/assets/javascripts/app/helpers/modal_helper.js

@@ -7,6 +7,7 @@
 
     modalBody.load(url, function(){
       $(id).find("#modalWaiter").remove();
+      autosize($("textarea", modalBody));
       $(id).trigger("modal:loaded");
     });
   };