DevTools: fix overlapping toolbars in Sources and SearchableViews

third_party/WebKit/Source/devtools/front_end/ui/searchableView.css

 /*
  * Copyright (c) 2014 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.
  */
 
 .search-bar {
     flex: 0 0 23px;
     background-color: #eee;
     border-top: 1px solid #ccc;
     display: flex;
     overflow: hidden;
+    z-index: 0;
 }
 
 .search-bar.replaceable {
     flex: 0 0 44px;
 }
 
 .search-toolbar {
     margin-top: -2px;
 }
 
@@ skipping 102 matching lines @@
     background-image: url(Images/searchNext.png), linear-gradient(rgb(168, 168, 168), rgb(116, 116, 116));
 }
 
 .search-results-matches {
     display: inline-block;
     text-align: right;
     font-size: 11px;
     padding: 0 4px;
     color: rgb(165, 165, 165);
 }