Otherwise the applypatch executable will fail to back up the source
file to /cache when patching the recovery image.
Bug: 74198354
Test: run applypatch from boot to recovery
Change-Id: I6e5b9cd06d6ed0b26066b779a348437ecf984b92
This class allows us to set the following locations dynamically:
cache_temp_source, last_command_file, stash_directory_base.
In the updater's main function, we reset the values of these variables
to their default locations in /cache; while we can set them to temp
files in unit tests or host simulation.
Test: unit tests pass
Change-Id: I528652650caa41373617ab055d41b1f1a4ec0f87
Tianjie Xu