Provide a way to enable stacktrace recovery in Android release build

[varahash]

As mentioned in https://github.com/Kotlin/kotlinx.coroutines/blob/master/ui/kotlinx-coroutines-android/README.md#optimization

When optimizations are enabled with R8 version 1.6.0 or later the following debugging features are permanently turned off to reduce the size of the resulting binary:

• Debugging mode
• Stacktrace recovery
• The internal assertions in the library are also permanently removed.

There is should be a way to opt-out this behaviour.

[Thomas-Vos]

Yes, please. I really need the stack trace of a kotlinx.coroutines.JobCancellationException so I can try to reproduce the reported crash. Is there a way to enable stack trace recovery in release builds?

[dkhalanskyjb]

See #3611 for some prior art.

[LouisCAD]

What is causing stacktrace recovery to not work after R8?
Is it rules that the kotlinx.coroutines library is embedding?

[qwwdfsad]

Yes, embedded rules are the main suspect here

[LouisCAD]

It'd be great to have those in a code-free extra artifact that the -android module depends on, and give us a way to exclude it.

[LouisCAD]

I mean, just using Gradle APIs should suffice to exclude it if it's in a separate artifact.