Fix a couple of memory leaks in tests.
Fix a potential case that length could be zero.
Bug: 23762183
Test: Ran unit tests, then ran valgrind on unit tests and verified no leaks.
Change-Id: I5f7602aa0204db0488a8e305250658cdb6e977d0
The MapsOffline code is still in development so I'm not testing it very
thoroughly yet.
Bug: 23762183
Test: All unit tests pass.
Change-Id: I77aeac62940cd95c489ee221afe02349bfe39671