Avoid retrying to read property block from a table when it does not exist.

Summary:
Avoid retrying to read property block from a table when it does not exist
in updating stats for compensating deletion entries.

In addition, ReadTableProperties() now returns Status::NotFound instead
of Status::Corruption when table properties does not exist in the file.

Test Plan:
make db_test -j32
export ROCKSDB_TESTS=CompactionDeleteionTrigger
./db_test

Reviewers: ljin, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21867