Bug 41927 [Dialogs] Selecting in PreferenceDialog generates too many invalid entries
20030825 If you select an entry, close the dialog and then reopen it selecting anotehr entry will result in a "this page has invalid values" although you selected nothing.
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferenceDialog.java
*/
	protected boolean showPage(IPreferenceNode node) {
		if (node == null)
			return false;
		
		if (node.getPage() == null)
			node.createPage();
		if (node.getPage() == null)
			return false;
		IPreferencePage newPage = node.getPage();
		if (newPage == currentPage)
			return true;
		if (currentPage != null) {
			if (!currentPage.okToLeave())
				return false;
		};
		IPreferencePage oldPage = currentPage;
		currentPage = newPage;
		
		currentPage.setContainer(this);
		
		
		if (currentPage.getControl() == null) {
			final boolean[] failed = { false };
			Platform.run(new ISafeRunnable() {
				public void run() {
					currentPage.createControl(pageContainer);
				}
				public void handleException(Throwable e) {
					failed[0] = true;