Destroying a bar manager via its Free method doesn't immediately remove built-in dock controls, which results in delayed updates to a form's ControlCount property

Create a TdxBarManager on Application.Mainform, will create additional 4 TdxDockControl instances in the form. This can be detected in TForm.ControlCount property.

However, when the TdxBarManager instance is free, the TForm.ControlCount value remain and didn't decrease. This issue may cause error (not always) in the following code (unit Forms.pas):

Delphi
procedure TraverseClients(Container: TWinControl);  
var  
  I: Integer;  
  Control: TControl;  
begin  
  if Container.Showing and not (csDesigning in Container.ComponentState) then  
    for I := 0 to Container.ControlCount - 1 do  
    begin  
      Control := Container.Controls[I];  
      if (csActionClient in Control.ControlStyle) and Control.Visible then  
          Control.InitiateAction;  
      if (Control is TWinControl) and (TWinControl(Control).ControlCount > 0) then  
        TraverseClients(TWinControl(Control));  
    end;  
end;  

To replay the problem, run the following code:

Delphi
var i1, i2, i3: Integer;  
    B: TdxBarManager;  
begin  
  // Get initial control count  
  i1 := Application.MainForm.ControlCount;  

  B := TdxBarManager.Create(Application.MainForm);  
  i2 := Application.MainForm.ControlCount;  

  // control count increased by 4 TdxDockControl  
  Assert(i2 = i1 + 4);  

  B.Free;  

  // After free TdxBarManager instance, control count didn't decrease  
  i3 := Application.MainForm.ControlCount;  
  Assert(i3 = i1);  
end;