Provide a small amount of padding in extension errors for the highlight border

chrome/browser/resources/extensions/extension_error.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. */
 
 .extension-error-list a {
   cursor: pointer;
 }
 
 .extension-error-list-contents {
   -webkit-transition: max-height 500ms ease-in-out;
@@ skipping 27 matching lines @@
 .extension-error-list-show-more {
   text-align: center;
   width: 100%;
 }
 
 .extension-error-list-show-more button {
   width: auto;
 }
 
 .extension-error-metadata {
+  -webkit-margin-after: 1px;
+  -webkit-margin-before: 1px;

[Dan Beam, 2014/09/26 01:42:19]

why not margin-(bottom|top)?

[Devlin, 2014/09/27 00:33:24]

I thought the -webkit variants were encouraged for these (even for bottom and
top).  For my own edification, is there a time when we prefer one of these over
the other (excluding the obvious case of preferring start/end for most things
due to LTR vs RTL distinctions)?

(And changed to margin-bottom\top).

[Dan Beam, 2014/09/27 01:27:41]

start/end have some useful properties for LTR/RTL.  before/after aren't as clear
to me as top/bottom, imo, and sound like ::before/::after...

+  -webkit-padding-end: 1px;
   display: flex;
   flex-direction: row;
-  width: 100%;
 }
 
 .extension-error-icon {
   -webkit-margin-end: 3px;
   -webkit-margin-start: 3px;
   height: 15px;
   vertical-align: middle;
   width: 15px;
 }
 
@@ skipping 18 matching lines @@
 .extension-error-severity-warning .extension-error-icon {
   content: url('extension_error_severity_warning.png');
 }
 
 .extension-error-severity-fatal .extension-error-message {
   color: rgba(200, 50, 50, 255);
 }
 .extension-error-severity-fatal .extension-error-icon {
   content: url('extension_error_severity_fatal.png');
 }