Test with ProGuard

[JakeWharton]

Refs #536

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• CHANGELOG.md's "Unreleased" section has been updated, if applicable.

[JakeWharton]

Blocked on:

java.lang.VerifyError: Bad type on operand stack
Exception Details:
  Location:
    kotlinx/coroutines/JobKt.invokeOnCompletion(Lkotlinx/coroutines/Job;ZLkotlinx/coroutines/JobNode;)Lkotlinx/coroutines/DisposableHandle; @40: invokeinterface
  Reason:
    Type 'kotlin/jvm/functions/Function1' (current frame, stack[3]) is not assignable to 'kotlinx/coroutines/JobKt__JobKt$invokeOnCompletion$1'
  Current Frame:
    bci: @40
    flags: { }
    locals: { 'kotlinx/coroutines/Job', integer, 'kotlinx/coroutines/JobNode' }
    stack: { 'kotlinx/coroutines/Job', integer, integer, 'kotlin/jvm/functions/Function1' }
  Bytecode:
    0000000: 2a1b 2c4d 3c59 4bc1 0007 9900 0d2a c000
    0000010: 071b 2cb6 000a b02a 2cb6 0009 1bbb 0005
    0000020: 592c b700 08c0 0002 b900 0b04 00b0
  Stackmap Table:
    same_frame(@23)

    at kotlinx.coroutines.JobKt__JobKt.invokeOnCompletion$default$7beb268f(Job.kt:351)
    at kotlinx.coroutines.CancellableContinuationImpl.installParentHandle(CancellableContinuationImpl.kt:23001)
    at kotlinx.coroutines.CancellableContinuationImpl.initCancellability(CancellableContinuationImpl.kt:126)
    at kotlinx.coroutines.DelayKt.delay-VtjQ1oo(Delay.kt:2178)

which I think is a ProGuard bug.

29: new           #5                  // class kotlinx/coroutines/JobKt__JobKt$invokeOnCompletion$1
32: dup
33: aload_2
34: invokespecial #8                  // Method kotlinx/coroutines/JobKt__JobKt$invokeOnCompletion$1."<init>":(Lkotlinx/coroutines/JobNode;)V
37: checkcast     #2                  // class kotlin/jvm/functions/Function1
40: invokeinterface #11,  4           // InterfaceMethod kotlinx/coroutines/Job.invokeOnCompletion$87b5a68:(ZZLkotlinx/coroutines/JobKt__JobKt$invokeOnCompletion$1;)Lkotlinx/coroutines/DisposableHandle;

The checkcast is entirely useless here.