Bug 94674 [Preferences] Preferences dialog separator under Title for pages does not stretch all the way across
The separator under the Header title for a preference page should stretch from the border of the sash to the far right with no margins in between.
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferenceDialog.java
IPreferenceNode node = findNodeMatching(getSelectedNodePreference());
		if (node == null) {
			IPreferenceNode[] nodes = preferenceManager.getRoot().getSubNodes();
			if (nodes.length > 0)
				node = nodes[0];
		}
		if (node != null) {
			getTreeViewer().setSelection(new StructuredSelection(node), true);
			
			getTreeViewer().getControl().setFocus();
		}
	}
	/**
	 * Display the given error message. The currently displayed message is saved
	 * and will be redisplayed when the error message is set to
	 * <code>null</code>.
	 * 
	 * @param newErrorMessage
	 *            the errorMessage to display or <code>null</code>
	 */
	public void setErrorMessage(String newErrorMessage) {
		if (newErrorMessage == null)
			messageArea.clearErrorMessage();
		else
			messageArea.updateText(newErrorMessage, IMessageProvider.ERROR);
	}
	/**
	 * Save the last known tree width.
	 * 
	 * @param width