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

Source/devtools/front_end/ui/View.js

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  * 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.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 84 matching lines @@
     },
 
     /**
      * @return {boolean}
      */
     isShowing: function()
     {
         return this._isShowing;
     },
 
+    /**
+     * @return {boolean}
+     */
+    _shouldHideOnDetach: function()
+    {
+        if (this._hideOnDetach)
+            return true;
+        for (var child of this._children) {
+            if (child._shouldHideOnDetach())
+                return true;
+        }
+        return false;
+    },
+
     setHideOnDetach: function()
     {
         this._hideOnDetach = true;
     },
 
     /**
      * @return {boolean}
      */
     _inNotification: function()
     {
@@ skipping 146 matching lines @@
      */
     detach: function(overrideHideOnDetach)
     {
         var parentElement = this.element.parentElement;
         if (!parentElement)
             return;
 
         if (this._parentIsShowing())
             this._processWillHide();
 
-        if (this._hideOnDetach && !overrideHideOnDetach) {
+        if (!overrideHideOnDetach && this._shouldHideOnDetach()) {
             this.element.classList.remove("visible");
             this._visible = false;
             if (this._parentIsShowing())
                 this._processWasHidden();
             if (this._parentView && this._hasNonZeroConstraints())
                 this._parentView.invalidateConstraints();
             return;
         }
 
         // Force legal removal
@@ skipping 370 matching lines @@
 {
     WebInspector.View.__assert(!child.__viewCounter && !child.__view, "Attempt to remove element containing view via regular DOM operation");
     return WebInspector.View._originalRemoveChild.call(this, child);
 }
 
 Element.prototype.removeChildren = function()
 {
     WebInspector.View.__assert(!this.__viewCounter, "Attempt to remove element containing view via regular DOM operation");
     WebInspector.View._originalRemoveChildren.call(this);
 }