Matan Lurey f0ed60a2a5 Make shell/platform/android IDE-friendly, and add documentation (flutter/engine#49612)
Closes https://github.com/flutter/flutter/issues/141043.

Nothing in this change should impact:

- End-user apps
- Testing and/or CI

I've added what I believe is the minimum required to get a reasonable
Android Studio experience with the `shell/platform/android` folder. More
could definitely be done, but this unblocks me (i.e.
https://github.com/flutter/flutter/issues/139702) and adds instructions
for the next person.

_I'm open to suggestions on how to improve this further, but unless they
are critical, I'd rather land this as-is and review your PRs tweaking my
documentation further (I have limited time to work exclusively on
docs)._

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Example after this:


![image](https://github.com/flutter/engine/assets/168174/97dfd46b-b617-4bb5-9144-0802d88e2864)
2024-01-09 14:01:04 -08:00
..