Bug 32893 Workspace Compatibility Problems 2.0 -> 2.1
Build 2.1 RC1 This PR collects problems related to opening a 2.0 workspace with 2.1.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/PreferenceConstants.java
* <p>
	 * Value is of type <code>String</code>: possible values are <code>
	 * UPDATE_ON_SAVE</code> or <code>
	 * UPDATE_WHILE_EDITING</code>.
	 * </p>
	 * 
	 * @see #UPDATE_ON_SAVE
	 * @see #UPDATE_WHILE_EDITING
	 */
	public static final String UPDATE_JAVA_VIEWS= "JavaUI.update"; 
	/**
	 * A string value used by the named preference <code>UPDATE_JAVA_VIEWS</code>
	 * 
	 * @see #UPDATE_JAVA_VIEWS
	 */
	public static final String UPDATE_ON_SAVE= "JavaUI.update.onSave"; 
	/**
	 * A string value used by the named preference <code>UPDATE_JAVA_VIEWS</code>
	 * 
	 * @see #UPDATE_JAVA_VIEWS
	 */
	public static final String UPDATE_WHILE_EDITING= "JavaUI.update.whileEditing"; 
	/**
	 * A named preference that holds the path of the Javadoc command used by the Javadoc creation wizard.
	 * <p>
	 * Value is of type <code>String</code>.
	 * </p>
	 */
	public static final String JAVADOC_COMMAND= "command"; 
	/**