Bug 202474 [Forms] Create a resource manager to share the bold font
If a FormToolkit is passed into FormEditor it is disposed upon disposal of the editor even though it may be shared.
bundles/org.eclipse.ui.forms/src/org/eclipse/ui/forms/widgets/FormToolkit.java
if (boldFont == null) {
				boldFont = FormUtil.createBoldFont(colors.getDisplay(),
						normalFont);
			}
		}
		public void dispose() {
			if (boldFont != null) {
				boldFont.dispose();
				boldFont = null;
			}
		}
	}
	/**
	 * Creates a toolkit that is self-sufficient (will manage its own colors).
	 * 
	 */
	public FormToolkit(Display display) {
		this(new FormColors(display));
	}
	/**
	 * Creates a toolkit that will use the provided (shared) colors. The toolkit
	 * will dispose the colors if and only if they are <b>not</b> marked as
	 * shared via the <code>markShared()</code> method.
	 * 
	 * @param colors
	 *            the shared colors
	 */
	public FormToolkit(FormColors colors) {
		this.colors = colors;
		initialize();