Check for null

fixes issue 4066
fixes issue 4067

Change-Id: Iaeada7d3db1d7ed9ffab8e8a30294a6f3eb59ba7
Reviewed-on: http://gerrit.dmdirc.com/1187
Reviewed-by: Gregory Holmes <greg@dmdirc.com>
Automatic-Compile: DMDirc Local Commits <dmdirc@googlemail.com>

src/com/dmdirc/addons/ui_swing/framemanager/buttonbar/ButtonBar.java

@@ -256,11 +256,11 @@ public final class ButtonBar implements FrameManager, ActionListener,
             /** {@inheritDoc} */
             @Override
             public void run() {
-                buttons.remove(window.getContainer());
-                relayout();
                 window.getContainer().removeNotificationListener(ButtonBar.this);
                 window.getContainer().removeFrameInfoListener(ButtonBar.this);
                 window.getContainer().removeSelectionListener(ButtonBar.this);
+                buttons.remove(window.getContainer());
+                relayout();
             }
         });
     }
@@ -383,7 +383,9 @@ public final class ButtonBar implements FrameManager, ActionListener,
             /** {@inheritDoc} */
             @Override
             public void run() {
-                buttons.get(window).setIcon(IconManager.getIconManager().getIcon(icon));
+                if (buttons.containsKey(window)) {
+                    buttons.get(window).setIcon(IconManager.getIconManager().getIcon(icon));
+                }
             }
         });
     }
@@ -396,7 +398,9 @@ public final class ButtonBar implements FrameManager, ActionListener,
             /** {@inheritDoc} */
             @Override
             public void run() {
-                buttons.get(window).setText(name);
+                if (buttons.containsKey(window)) {
+                    buttons.get(window).setText(name);
+                }
             }
         });
     }