Bug 33550 [Dialogs] Dialog should support remembering size and position
There are several dialogs that remember its size and position. Since restore the size and considering screen size and font changes isn't trivial JFace's Dialog class should support remembering and restoring size and position. These would realy ease the task for subclasses. May be you can steel the code from OpenTypeSelectionDialog.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/Dialog.java
* 
     * @param fontMetrics
     *            used in performing the conversion
     * @param chars
     *            the number of characters
     * @return the number of pixels
     * @since 2.0
     */
    public static int convertWidthInCharsToPixels(FontMetrics fontMetrics,
            int chars) {
        return fontMetrics.getAverageCharWidth() * chars;
    }
    /**
     * Shortens the given text <code>textValue</code> so that its width in
     * pixels does not exceed the width of the given control. Overrides
     * characters in the center of the original string with an ellipsis ("...")
     * if necessary. If a <code>null</code> value is given, <code>null</code>
     * is returned.
     * 
     * @param textValue
     *            the original string or <code>null</code>
     * @param control
     *            the control the string will be displayed on
     * @return the string to display, or <code>null</code> if null was passed
     *         in
     * 
     * @since 3.0
     */
    public static String shortenText(String textValue, Control control) {
        if (textValue == null)