gh-159645: Fix --async-aware profiles showing event loop frames under tasks - #159679

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hummm I don’t think this is a correct fix. FRAME_EXECUTING does not guarantee that the task frame is in the thread stack.

For example, when spin() yields at await asyncio.sleep(0), _YIELD_VALUE removes its frame before it updates gi_frame_state. A sample between those writes sees FRAME_EXECUTING, but the thread stack already leads back to the event loop:

Handle._run -> BaseEventLoop._run_once -> BaseEventLoop.run_forever

parse_async_frame_chain() never reaches the spin() frame, yet it returns success. Those event-loop frames then replace the task’s logical coroutine chain. This also affects --blocking, since the process can stop between those writes.

Thanks! I'll think about proper solution