Bug 132821 [Dialogs] Stored Dialog location and size invalid after changing font
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/Dialog.java
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));
		applyDialogFont(composite);
		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>.
	 * 
	 * @param id
	 *            the id of the button to look for
	 * 
	 * @return the button for the ID or <code>null</code>
	 * 
	 * @see #createButton(Composite, int, String, boolean)
	 * @since 2.0
	 */
	protected Button getButton(int id) {
		return (Button) buttons.get(new Integer(id));
	}
	/**
	 * Returns the button bar control.
	 * <p>