Java: remove stubs/android directory

[jcogs33]

Summary:
This PR removes the old stubs/android directory and replaces anywhere it is used with stubs/google-android-9.0.0 instead.

Description:

• Searched for usages of stubs/android and found that it was only used in two options files. Updated these files to use stubs/google-android-9.0.0 instead.
• Ran the tests related to these options files to confirm that they still work when using stubs/google-android-9.0.0. Since they worked after the switch, there did not appear to be any need to generate additional stubs in stubs/google-android-9.0.0 for them.
• Deleted the stubs/android directory.

Consideration:

• I noticed that a com/android/internal/R.java file existed in stubs/android but not in stubs/google-android-9.0.0. I did not move this file to stubs/google-android-9.0.0 since it does not seem that any tests are dependent on it (based on the Java Language Tests check passing without it). Let me know if this file should be moved to stubs/google-android-9.0.0 instead of being removed.
• Let me know if there is anything else that needs to be updated/considered when removing this directory.

[atorralba]

This is great, thank you! The R.java file is auto-generated in real Android applications, so it makes sense we don't need it in our tests.