Scroll buttons are not getting displayed properly in JTabbedPane with SCROLL_TAB_LAYOUT on changing the tab placement at runtime using setTabPlacement() method.

Find attached test case with the bug report.

To Reproduce the bug :

1) Compile and run the attached Java File.
2) In this Java class, JTabbedPane is constructed with tab placement as TOP, but modified the tab placement to RIGHT.

Result : The scroll buttons are not getting displayed even though it is unable to display all the tabs.