Bug 283442 [UI] Refactor the rendering class names
In order to bring the model closer to the way in which we talk about it we should re-factor it to remove references to 'factory'. For now the re-factoring will to replace 'PartRenderer' with 'PartRenderingEngine' and to replace '<xxx>Factory' with '<xxx>Renderer'. Post 0.9 we expect to change these again but this will make the initial story clearer.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/workbench/ui/renderers/PartFactory.java
protected IEclipseContext getContextForParent(MPart<?> part) {
		MPart<?> parent = part.getParent();
		while (parent != null) {
			if (parent.getContext() != null) {
				return parent.getContext();
			}
			parent = parent.getParent();
		}
		return context;
	}
	/**
	 * Return a context for this part.
	 * 
	 * @param part
	 *            the part to start searching from
	 * @return the closest context, or global context if none in the hierarchy
	 */
	protected IEclipseContext getContext(MPart<?> part) {
		if (part.getContext() != null) {
			return part.getContext();
		}
		return getContextForParent(part);
	}
	protected IEclipseContext getToplevelContext(MPart<?> part) {
		IEclipseContext result = null;
		if (part.getParent() != null) {
			result = getToplevelContext(part.getParent());
		}
		if (result == null) {
			result = part.getContext();