DevTools: do not detach views that should be hidden upon detach.

Source/devtools/front_end/splitView.css

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * 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 44 matching lines @@
 }
 
 .split-view.vbox > .split-view-resizer {
     position: absolute;
     left: 0;
     right: 0;
     height: 6px;
     z-index: 500;
 }
 
+.split-view.hbox.split-view-first-is-sidebar {
+    flex-direction: row-reverse !important;
+}
+
+.split-view.vbox.split-view-first-is-sidebar {
+    flex-direction: column-reverse !important;
+}
+
 .split-view-resizer-border {
     pointer-events: none;
 }
 
 .split-view.vbox > .split-view-resizer > .split-view-resizer-border {
     width: 100%;
     margin-top: 3px;
     height: 1px;
     border-top: 1px solid rgb(64%, 64%, 64%);
 }
@@ skipping 74 matching lines @@
 
 .split-view button.bottom-sidebar-show-hide-button.toggled-show > .glyph {
     -webkit-mask-position: -296px -76px; /* <| */
     transform: rotate(90deg);
 }
 
 .split-view button.bottom-sidebar-show-hide-button.toggled-hide > .glyph {
     -webkit-mask-position: -264px -76px; /* >| */
     transform: rotate(90deg);
 }