* <li>when <tt>split == true</tt>, it is common to specify a
* <tt>{@link Ext.SplitBar#minSize minSize}</tt> and <tt>{@link Ext.SplitBar#maxSize maxSize}</tt>
* for the {@link Ext.BoxComponent BoxComponent} representing the region. These are not native
* configs of {@link Ext.BoxComponent BoxComponent}, and are used only by this class.</li>
* <li>if <tt>{@link #collapseMode} = 'mini'</tt> requires <tt>split = true</tt> to reserve space
* <li>when <tt>split == true</tt>, it is common to specify a
* <tt>{@link Ext.SplitBar#minSize minSize}</tt> and <tt>{@link Ext.SplitBar#maxSize maxSize}</tt>
* for the {@link Ext.BoxComponent BoxComponent} representing the region. These are not native
* configs of {@link Ext.BoxComponent BoxComponent}, and are used only by this class.</li>
* <li>if <tt>{@link #collapseMode} = 'mini'</tt> requires <tt>split = true</tt> to reserve space