deal with some potential int overflows

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/compress/trunk@1619657 13f79535-47bb-0310-9956-ffa450edef68
Inflater knows the amount of data it has written

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/compress/trunk@1619661 13f79535-47bb-0310-9956-ffa450edef68