"/data/data" directory is a data directory for user 0. If there are multiple users on the device, each will have a separate data dir indicated by their user id in "/data/user/[user_id]" i.e.
"/data/user/0" -> "data/data" (user 0 directory)
"/data/user/10" (user 10 directory)

When we run a test in a secondary user (like user 10), AppDataDirGuesser.guess() will return null, and the test will fail unless "dexmaker.dexcache" has been explicitly specified.

To fix this:

• We would need to guess the ID of the user running the test. This can be fetched through android APIs, like android.os.Process, but dexmaker doesn't depend on the android library.
• Try to find a directory by iterating over possible user IDs, capping at some reasonable maximum. This is hacky and limited, but might be the only option if we can't depend on android