GH-52 Fixed keyboard navigation

 - ClosableTabbledPane is not a focus cycle root
 - CloseButton is focusable

Author: jisedlac

visualvm/core/src/com/sun/tools/visualvm/core/ui/DataSourceWindowTabbedPane.java

@@ -89,6 +89,9 @@ private static boolean isWindowsLaF () {
 
     tabpane = TabbedPaneFactory.createCloseButtonTabbedPane();
     tabpane.setTabLayoutPolicy(JTabbedPane.WRAP_TAB_LAYOUT);
+    
+    // GH-52 - true would break Tab navigation
+    tabpane.setFocusCycleRoot(false);
 
     // Clear default border for fill up the entire DataSourceWindow
     tabpane.setOpaque(false);

visualvm/core/src/com/sun/tools/visualvm/core/ui/components/DisplayArea.java

@@ -455,6 +455,7 @@ private void initComponents() {
 //            ImageIcon closeIcon = new ImageIcon(DisplayArea.class.getResource("/com/sun/tools/visualvm/core/ui/resources/closePanel.png")); // NOI18N
 //            closeButton = new DisplayAreaSupport.ImageIconButton(closeIcon);
             closeButton = CloseButtonFactory.createBigCloseButton();
+            closeButton.setFocusable(true); // GH-52 - enable closing the view using keyboard
             closeButton.setToolTipText(NbBundle.getMessage(DisplayArea.class, "ToolTip_Hide")); // NOI18N
             closeButton.addActionListener(new ActionListener() {
                     public void actionPerformed(ActionEvent e) { getParent().getParent().setVisible(false); }