Bug 108700 [typing] Automatically close parenthesis does not work when content assist popup is up
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/java/LazyJavaCompletionProposal.java
/**
	 * A class to simplify tracking a reference position in a document.
	 */
	static final class ReferenceTracker {
	
		
		private static final String CATEGORY= "reference_position"; 
		
		private final IPositionUpdater fPositionUpdater= new DefaultPositionUpdater(CATEGORY);
		
		private final Position fPosition= new Position(0);
	
		/**
		 * Called before document changes occur. It must be followed by a call to postReplace().
		 *
		 * @param document the document on which to track the reference position.