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
/**
	 * Returns the proposal selected in the proposal selector.
	 * 
	 * @return the selected proposal
	 * @since 2.0
	 */
	private ICompletionProposal getSelectedProposal() {
		int i= fProposalTable.getSelectionIndex();
		if (i < 0 || i >= fFilteredProposals.length)
			return null;
		return fFilteredProposals[i];
	}
		
	/**
	 * Takes the selected proposal and applies it.
	 * 
	 * @param stateMask the state mask
	 * @since 2.1
	 */
	private void selectProposalWithMask(int stateMask) {
		ICompletionProposal p= getSelectedProposal();
		hide();
		if (p != null)
			insertProposal(p, (char) 0, stateMask, fViewer.getSelectedRange().x);
	}
	
	/**
	 * Applies the given proposal at the given offset. The given character is the
	 * one that triggered the insertion of this proposal.