Instead of attaching just the CompletionOnType node attach the whole
LocalDeclaration node so the correct expression get resolved
which provide required type information in the computing expected types.

Change-Id: Ic59d5ad8bbf5b39e93c35040e6b20f8253754144
Signed-off-by: Gayan Perera <gayanper@gmail.com>
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.core/+/189412
Tested-by: JDT Bot <jdt-bot@eclipse.org>
Reviewed-by: Jay Arthanareeswaran <jarthana@in.ibm.com>