Bug 329930 Resetting a perspective while its active part is not defined in the perspective causes the perspective to not have an active part after the reset
1. Window > Show View > Console 2. Window > Reset Perspective... > OK 3. No parts are active.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/workbench/modeling/EPartService.java
*            the part to activate, must not be <code>null</code>
	 */
	public void activate(MPart part);
	/**
	 * Activates the given part. The part will be brought to top (if necessary) and, if
	 * {@code requiresFocus} is true, then granted focus.
	 * 
	 * @param part
	 *            the part to activate, must not be <code>null</code>
	 * @param requiresFocus
	 *            if true, then also cause the part to acquire focus
	 */
	public void activate(MPart part, boolean requiresFocus);
	/**
	 * Brings this part to the top so that it will become visible to the end user. This does not
	 * imply that the part will be granted focus.
	 * 
	 * @param part
	 *            the part to bring to top
	 */
	public void bringToTop(MPart part);
	/**
	 * Finds and returns a part with the given id.
	 * 
	 * @param id
	 *            the id of the part to search for, must not be <code>null</code>
	 * @return the part with the specified id, or <code>null</code> if no such part could be found
	 */
	public MPart findPart(String id);
	/**