[Chromecast] Reduce min timestamp stability time

The original value of 1sec was needed to have sufficient time to establish an
accurate reference timestamp. With new audio HAL code provided by the SoM
vendor that improves timestamp jitter significantly, we can reduce the
stability time. This has the benefit of a faster playback startup time.

Bug: internal b/78129008
Test: playback tests and obverving startup times in logs
Change-Id: I2bf9a21b32dc5e6b0cf400d1d195099e56b517a7
Reviewed-on: https://chromium-review.googlesource.com/1024312Reviewed-by: Kenneth MacKay <kmackay@chromium.org>
Commit-Queue: Chris Kuiper <ckuiper@chromium.org>
Cr-Commit-Position: refs/heads/master@{#552798}

chromecast/media/cma/backend/android/java/src/org/chromium/chromecast/cma/backend/android/AudioSinkAudioTrackImpl.java

@@ -110,7 +110,7 @@ class AudioSinkAudioTrackImpl {
     private static final int MIN_TIMESTAMP_STABILITY_CNT = 3;
     // Minimum time timestamps need to be stable to make it a valid reference point at startup or
     // after an underrun event. This is an additional safeguard.
-    private static final long MIN_TIMESTAMP_STABILITY_TIME_NSEC = SEC_IN_NSEC;
+    private static final long MIN_TIMESTAMP_STABILITY_TIME_NSEC = 150 * USEC_IN_NSEC;
     // After startup, any timestamp deviating more than this amount is ignored.
     private static final long TSTAMP_DEV_THRESHOLD_TO_IGNORE_NSEC = 500 * USEC_IN_NSEC;
     // Don't ignore timestamps for longer than this amount of time.