Bug 73027 [Dialogs] Buttons are too high
I20040831 Buttons are no longer oval but have a rounded rectangle shape (see first screenshot). The second screenshot shows how buttons using the small system font should look like.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/Dialog.java
*/
    private static void applyDialogFont(Control control, Font dialogFont) {
        if (hasDefaultFont(control))
            control.setFont(dialogFont);
        if (control instanceof Composite) {
            Control[] children = ((Composite) control).getChildren();
            for (int i = 0; i < children.length; i++)
                applyDialogFont(children[i], dialogFont);
        }
    }
    /**
     * Return whether or not this control has the same font as it's default.
     * 
     * @param control
     *            Control
     * @return boolean
     */
    private static boolean hasDefaultFont(Control control) {
        FontData[] controlFontData = control.getFont().getFontData();
        FontData[] defaultFontData = getDefaultFont(control).getFontData();
        if (controlFontData.length == defaultFontData.length) {
            for (int i = 0; i < controlFontData.length; i++) {
                if (controlFontData[i].equals(defaultFontData[i]))
                    continue;
                return false;
            }
            return true;
        }
        return false;
    }