Audio Policy: add flag for input stream sharing logic fix

        "This feature helps reduce audio glitching caused by low priority blocking threads."

    bug: "209491695"

}

flag {

    name: "fix_input_sharing_logic"

    namespace: "media_audio"

    description:

        "Fix the audio policy logic that decides to reuse or close "

        "input streams when resources are exhausted"

    bug: "338446410"

}