Fix [2520066]: Don't clean up dead monsters if they're quietly drained

to death in melee, to avoid messages like "You drained INVALID MONSTER!".

git-svn-id: https://crawl-ref.svn.sourceforge.net/svnroot/crawl-ref/trunk@8597 c06c8d41-db1a-0410-9941-cceddc491573

Created by  dolorous  on January 19, 2009
BJ63PXJSMITJY6T2AQGN4S3PA6C6Q5KNZNFP4Z2DKD4EQVD5YEUQC
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