Fix crashing StrictJarFile due to doubled closing.

If the constuctor throws, then the handles would be closed without
setting "closed" to true. As a result, the finalizer would close
the handles again, which would cause a crash on the native side.

Test: Unit tests are no longer flaky.
Bug: 33301253
Change-Id: I527ba38d5d65ce844258d894441d4fe16bac6e23