Bug 163360 [Field Assist] - API - Provide ControlDecoration constructor without specifying decoration
Currently you can only create a ControlDecoration by specifying the control and the decoration in the constructor. This works nicely when the decoration is static (ie, always content assist). But there are use cases where the decoration changes depending on the state of the field, and at creation time, it's not clear which decoration will be set. Having a constructor that doesn't require a decoration would be nice.
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ControlDecoration.java
showHoverText(text, control);
	}
	/**
	 * Hide any hover popups that are currently showing on the control. When
	 * {@link #setShowHover(boolean)} has been set to <code>true</code>, a
	 * decoration's description text will be shown in an info hover over the
	 * field's control as long as the mouse hovers over the decoration, and will
	 * be hidden when the mouse exits the decoration. This method can be used to
	 * hide a hover, whether it was shown explicitly using
	 * {@link #showHoverText(String)}, or was showing because the user was
	 * hovering in the decoration.
	 * <p>
	 * This message has no effect if there is no current hover.
	 * 
	 */
	public void hideHover() {
		if (hover != null) {
			hover.setVisible(false);
		}
	}
	/**
	 * Show the control decoration. This message has no effect if the decoration
	 * is already showing. If {@link #setShowOnlyOnFocus(boolean)} is set to
	 * <code>true</code>, the decoration will only be shown if the control
	 * has focus.
	 */
	public void show() {
		if (!visible) {
			visible = true;
			update();