Feedback dialog visual tweaks

ui/webui/resources/css/apps/common.css

 /* Copyright 2013 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file. */
 
 button.white-button,
 button.blue-button {
   border: 5px solid transparent;
   box-sizing: content-box;
   cursor: default;
+  font-size: 14px;
   height: 21px;
   line-height: 21px;
   margin: 0;
   min-height: 21px;
   min-width: 55px;
   padding: 0 10px;
   position: relative;
   outline: none;
   text-align: center;
   z-index: 1;
@@ skipping 140 matching lines @@
   background-image: -webkit-image-set(
     url(chrome://resources/images/apps/checkbox_focused_checked.png) 1x,
     url(chrome://resources/images/2x/apps/checkbox_focused_checked.png) 2x);
 }
 
 input[type='checkbox']:disabled:checked::after {
   background-image: -webkit-image-set(
     url(chrome://resources/images/apps/checkbox_checked_inactive.png) 1x,
     url(chrome://resources/images/2x/apps/checkbox_checked_inactive.png) 2x);
 }