DevTools: migrate EventListenersSidebarPane to shadow

third_party/WebKit/Source/devtools/front_end/components/breakpointsList.css

 /*
  * Copyright (C) 2006, 2007, 2008 Apple Inc.  All rights reserved.
  * Copyright (C) 2009 Anthony Ricaud <rik@webkit.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 105 matching lines @@
 li.breakpoint-hit .breakpoint-hit-marker {
     background-color: rgb(255, 255, 194);
     height: 18px;
     left: 0;
     margin-top: -16px;
     position: absolute;
     right: 0;
     z-index: -1;
 }
 
-.event-listener-breakpoints {
-    margin: 0;
-    padding: 2px 4px;
-    min-height: 18px;
-}
-
 .dom-breakpoints-list > li {
     display: flex;
 }
 
 .dom-breakpoints-list .dom-breakpoint > div {
     overflow: hidden;
     text-overflow: ellipsis;
 }