Use wxDELETE() and wxDELETEA() when possible.

Use wxDELETE[A]() functions which automatically NULL out their arguments after
deleting them instead of doing it manually.

Closes #9685.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@64656 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/univ/scrolbar.cpp

@@ -933,11 +933,7 @@ void wxStdScrollBarInputHandler::StopScrolling(wxScrollBar *control)
 
     m_btnCapture = -1;
 
-    if ( m_timerScroll )
-    {
-        delete m_timerScroll;
-        m_timerScroll = NULL;
-    }
+    wxDELETE(m_timerScroll);
 
     // unpress the arrow and highlight the current element
     Press(control, false);