Remove pre-aidegen IDE support logic

This has apparently been racy ever since
https://android-review.googlesource.com/c/platform/build/+/971925
and isn't generally useful anymore, as aidegen has taken over.

Bug: 193095826
Test: treehugger
Change-Id: I09b6b340b84d1476a574b302db520210561a4e5e