because "local" is null

Change-Id: Idb34042714763f7d0b04da57ffc57bc62dc6fa3e
Also-by: Andrey Loskutov <loskutov@gmx.de>
Signed-off-by: Stephan Herrmann <stephan.herrmann@berlin.de>
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.core/+/185836
Tested-by: JDT Bot <jdt-bot@eclipse.org>