When loading dex files from APKs, eagerly do checksums checks.

When we create the OatFile/VdexFile, and the dex files are stored in the
APK, we fetch them directly from the APK. To avoid reading the APK again
when OatFileAssistant wants to check checksums, we do the checksums
checks eagerly.

Test: test.py
Bug: 260862144
Change-Id: I2809b3698e11aeff47c0c8616dfff6a5483471ca
3 files changed