Downgrades to SDL2 2.0.9

[AndreMiras]

Actually simply reverted few files:

git checkout master -- \
    pythonforandroid/recipes/sdl2/__init__.py \
    pythonforandroid/bootstraps/sdl2/build/src/patches/SDLActivity.java.patch \
    pythonforandroid/bootstraps/sdl2/build/src/main/java/org/kivy/android/PythonActivity.java

• fixes App exists immediately when importing kivy.core.window.Window #2167
• fixes Issues introduced by PR #2113 (SDL2) #2169

[AndreMiras]

This fixes the issue referenced above.
I could run all the apps like before (including test apps for both architectures)

[inclement]

Looks good. The details of the PythonActivity change aren't entirely obvious to me, but I totally believe it's correct. Do you think it's worth logging somewhere (e.g. another issue) what you had to revert, so it's easier to go back to newer sdl2 versions later?

[AndreMiras]

Thanks for the review/approval!
I also don't know most of the details to be honest 😅
I'm not sure it's needed to log it somewhere else as the revert command is in the commit body (and this PR comments).
Basically I reverted the part of the PR #2113 (1b887be) that were concerning the version as I wanted to keep the SDL extract part.
To see and later re-apply the part that got reverted we could:

git show 1b887bed09a7ec19bfa00c9fb69a54e3f60a2328 -- \
    pythonforandroid/recipes/sdl2/__init__.py \
    pythonforandroid/bootstraps/sdl2/build/src/patches/SDLActivity.java.patch \
    pythonforandroid/bootstraps/sdl2/build/src/main/java/org/kivy/android/PythonActivity.java

That should be enough I think otherwise yes it doesn't hurt to create a reminder task with theses details I suppose