Bug 294462 [FieldAssist] ControlDecoration#showHoverText doesn't check if the widget is visible
If the HOVER-Text is set on decoration of a widget which is invisible the Hover-Shell is still poping up because it doesn't check if the control is invisible make the Hover appearing somewhere on the screen.
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ControlDecoration.java
return;
		}
		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) {