Bug 327825 Activated part in current perspective has its tab item granted focus when switching perspectives
1. Activate the 'Outline' view. 2. Window > Open Perspective > Debug 3. The tab item of the 'Outline' view gets focus.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/PartServiceImpl.java
if (newActivePart == null) {
				modelService.bringToTop(perspective);
				perspective.getContext().activate();
			} else {
				activate(newActivePart, true, false);
			}
		}
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.e4.ui.workbench.modeling.EPartService#activate(org.eclipse.e4.ui.model.application
	 * .MPart)
	 */
	public void activate(MPart part) {
		activate(part, true);
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.e4.ui.workbench.modeling.EPartService#activate(org.eclipse.e4.ui.model.application
	 * .MPart,boolean)
	 */
	public void activate(MPart part, boolean requiresFocus) {
		activate(part, requiresFocus, true);
	}
	private void activate(MPart part, boolean requiresFocus, boolean activateBranch) {