Bug 156456 [Forms] widgets accept focus even though they can't do anything with it
Many of the widgets in the Forms library (Section, BusyIndicator, FormHeading) will accept keyboard focus even though they can't do anything with it. The impact is that when someone calls setFocus on a Form that contains a FormHeading at its top (which is quite common), keyboard focus ends up nowhere. Looking at the patterns in SWT, it appears that the correct protocol is for controls to return false from setFocus if they can't do anything with the focus so that the caller can try assigning focus somewhere else.
bundles/org.eclipse.ui.forms/src/org/eclipse/ui/forms/widgets/ExpandableComposite.java
public void setActiveToggleColor(Color c) {
		if (toggle != null)
			toggle.setHoverDecorationColor(c);
	}
	/**
	 * Sets the fonts of all the custom controls in the expandable.
	 */
	public void setFont(Font font) {
		super.setFont(font);
		if (textLabel != null)
			textLabel.setFont(font);
		if (toggle != null)
			toggle.setFont(font);
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.swt.widgets.Control#setEnabled(boolean)
	 */
	public void setEnabled(boolean enabled) {
		if (textLabel != null)
			textLabel.setEnabled(enabled);
		if (toggle != null)
			toggle.setEnabled(enabled);
		super.setEnabled(enabled);
	}
	/**
	 * Sets the client of this expandable composite. The client must not be
	 * <samp>null </samp> and must be a direct child of this container.
	 *