Bug 26109 [Dialogs] Need a FormData version of the button sizing API
The button sizing API in Dialog assumes the developer wants a GridData. We should promote the FormData version in PathVariablesDialog to Dialog.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/Dialog.java
* </pre>
 *
 * @param parent the parent composite to contain the dialog area
 * @return the dialog area control
 */
protected Control createDialogArea(Composite parent) {
	
	Composite composite = new Composite(parent, SWT.NONE);
	GridLayout layout = new GridLayout();
	layout.marginHeight = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_MARGIN);
	layout.marginWidth = convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_MARGIN);
	layout.verticalSpacing = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_SPACING);
	layout.horizontalSpacing = convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_SPACING);
	composite.setLayout(layout);
	composite.setLayoutData(new GridData(GridData.FILL_BOTH));
	composite.setFont(parent.getFont());
	return composite;
}
/**
 * Returns the button created by the method <code>createButton</code>
 * for the specified ID as defined on <code>IDialogConstants</code>. If 
 * <code>createButton</code> was never called with this ID, or 
 * if <code>createButton</code> is overridden, this method will return
 * <code>null</code>.
 * 
 * @return the button for the ID or <code>null</code>
 * 
 * @see createButton
 * @since 2.0
 */