Dismiss infobar if it's dismissable on board save

Fixes https://gitlab.com/kicad/code/kicad/-/issues/7071

common/widgets/infobar.cpp

@@ -275,6 +275,22 @@ void WX_INFOBAR::RemoveAllButtons()
 }
 
 
+bool WX_INFOBAR::HasCloseButton() const
+{
+    wxSizer* sizer = GetSizer();
+
+    if( sizer->GetItemCount() == 0 )
+        return false;
+
+    if( sizer->GetItem( sizer->GetItemCount() - 1 )->IsSpacer() )
+        return false;
+
+    wxSizerItem* item = sizer->GetItem( sizer->GetItemCount() - 1 );
+
+    return ( item->GetWindow()->GetId() == ID_CLOSE_INFOBAR );
+}
+
+
 void WX_INFOBAR::onShowInfoBar( wxCommandEvent& aEvent )
 {
     RemoveAllButtons();

include/widgets/infobar.h

@@ -130,6 +130,8 @@ public:
      */
     void RemoveAllButtons();
 
+    bool HasCloseButton() const;
+
     /**
      * Provide a callback to be called when the infobar is dismissed (either by user action
      * or timer).

pcbnew/files.cpp

@@ -935,6 +935,10 @@ bool PCB_EDIT_FRAME::SavePcbFile( const wxString& aFileName, bool addToHistory,
 
     SetStatusText( lowerTxt, 0 );
 
+    // Get rid of the old version conversion warning, or any other dismissable warning :)
+    if( m_infoBar->IsShown() && m_infoBar->HasCloseButton() )
+        m_infoBar->Dismiss();
+
     GetScreen()->ClrModify();
     GetScreen()->ClrSave();
     return true;