Bug 126233 [FieldAssist] DecoratedField should not automatically reserve space on field ends
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/DecoratedField.java
* @param decoration
	 *            the decoration to be hidden.
	 */
	public void updateDecoration(FieldDecoration decoration) {
		FieldDecorationData data = getDecorationData(decoration);
		if (data == null)
			return;
		if (data.label != null) {
			data.label.setImage(decoration.getImage());
			
			
			if (data.label.getVisible() == true && hover != null) {
				showHoverText(decoration.getDescription(), data.label);
			}
		}
	}
	/*
	 * Set the visibility of the specified decoration data. This method does not
	 * change the visibility value stored in the decData, but instead consults
	 * it to determine how the visibility should be changed. This method is
	 * called any time visibility of a decoration might change, whether by
	 * client API or focus changes.
	 */
	private void setVisible(FieldDecorationData decData, boolean visible) {
		
		
		if (visible && decData.visible)
			decData.label.setVisible(true);
		else
			decData.label.setVisible(false);