Bug 216811 [Markers] ExtendedMarkersView#setFocus doesn't
The result is that focus is lost if you drag the view to another stack... The most common implementation seems to be 'viewer.getControl().setFocus()... To test: select an element in the Problems or Tasks view. Drag the view to a new location (could be in an existing stack or a new one) notice that while the view is the active view the arrow keys don't navigate...
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/views/markers/ExtendedMarkersView.java
return updateJob;
	}
	/**
	 * Return the object that is the input to the viewer.
	 * 
	 * @return Object
	 */
	Object getViewerInput() {
		return viewer.getInput();
	}
	/**
	 * Get all of the fields visible in the receiver.
	 * 
	 * @return MarkerField[]
	 */
	MarkerField[] getVisibleFields() {
		return builder.getVisibleFields();
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.part.ViewPart#init(org.eclipse.ui.IViewSite,
	 *      org.eclipse.ui.IMemento)
	 */
	public void init(IViewSite site, IMemento memento) throws PartInitException {
		super.init(site, memento);
		MarkerContentGenerator generator = null;
		if (memento != null) {
			generator = MarkerSupportRegistry.getInstance().getGenerator(
					memento.getString(TAG_GENERATOR));