Allow use of same zip checksum for multiple dex files.

Dex containers store multiple dex files in the same zip entry.

Fix VdexFile::ComputeClassStatus not to rely on the uniqueness.

Profile loading verifies just (filename, zip-checksum) tuples.

Bug: 455778210
Test: art_libdexfile_tests
Flag: EXEMPT BUGFIX
Change-Id: I27546da18f0b59913c9af8b38eca0b0a8457ec28