Bug 42587 Left over from content assist
M3 - set preference that content assist should overwrite - open content assist on some word so that the rest of the word is indicated to be overwritten - transfer focus to the content assist widget using TAB - Esc -> overwrite indication is still there
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/link/contentassist/CompletionProposalPopup2.java
* @return <code>true</code> if character belongs to the list
	 * @since 2.0
	 */
	private boolean contains(char[] characters, char c) {
		
		if (characters == null)
			return false;
			
		for (int i= 0; i < characters.length; i++) {
			if (c == characters[i])
				return true;
		}
		
		return false;
	}
	
	/*
	 * @see IEventConsumer#processEvent(VerifyEvent)
	 */
	public void processEvent(VerifyEvent e) {
	}
	
	/**
	 * Filters the displayed proposal based on the given cursor position and the 
	 * offset of the original invocation of the content assistant.
	 */
	private void filterProposals() {
		++ fInvocationCounter;
		Control control= fViewer.getTextWidget();
		control.getDisplay().asyncExec(new Runnable() {