Bug 320285 Messages inteneded for developers in the error log
The message "unsupported: isEditorAreaVisible" appears in the error log during the normal run of e4 SDK. (For instance, starting the e4 SDK on an clean workspace produces two of those messages.)
bundles/org.eclipse.e4.ui.workbench.addons.swt/src/org/eclipse/e4/ui/workbench/addons/perspectiveswitcher/PerspectiveSwitcher.java
Point point = psTB.toDisplay(bounds.x, bounds.y + bounds.height);
		menu.setLocation(point.x, point.y);
		menu.setVisible(true);
		menu.addMenuListener(new MenuListener() {
			public void menuHidden(MenuEvent e) {
				psTB.getDisplay().asyncExec(new Runnable() {
					public void run() {
						menu.dispose();
					}
				});
			}
			public void menuShown(MenuEvent e) {
				
			}
		});
	}
	private void addCloseItem(final Menu menu) {
		MenuItem menuItem = new MenuItem(menu, SWT.NONE);
		menuItem.setText("&Close");
		menuItem.addSelectionListener(new SelectionAdapter() {
			public void widgetSelected(SelectionEvent e) {
				MPerspective persp = (MPerspective) menu.getData();
				if (persp != null)
					closePerspective(persp);
			}
		});
	}
	private void closePerspective(MPerspective persp) {
		MWindow win = modelService.getTopLevelWindowFor(persp);
		IWorkbenchPage page = win.getContext().get(IWorkbenchPage.class);