Bug 97196 [quick fix] visibility linked proposals eat space
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/correction/LinkedCorrectionProposal.java
* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#validate(org.eclipse.jface.text.IDocument, int, org.eclipse.jface.text.DocumentEvent)
		 */
		public boolean validate(IDocument document, int offset, DocumentEvent event) {
			
			String insert= getDisplayString();
			if (insert == null)
				return false;
			int off;
			Position pos= getCurrentPosition(offset);
			if (pos != null) {
				off= pos.getOffset();
			} else {
				off= Math.max(0, offset - insert.length());
			}
			int length= offset - off;
			if (offset <= document.getLength()) {
				try {
					String content= document.get(off, length);
					if (insert.startsWith(content))
						return true;
				} catch (BadLocationException e) {
					JavaPlugin.log(e);
					
				}
			}
			return false;
		}
	}
}