PASS Test sequence AppendMode appendBuffer(first media segment)
PASS Test sequence AppendMode appendBuffer(second media segment)
PASS Test sequence AppendMode appendBuffer(second media segment, then first media segment)
+PASS Test sequence AppendMode appendBuffer back-to-back(first media segment, then second media segment)
+PASS Test sequence AppendMode appendBuffer after setting TSO > 0
+PASS Test sequence AppendMode appendBuffer with large gap between segments.
+PASS Test sequence AppendMode appendBuffer fully before the appendwindow.
+PASS Test sequence AppendMode appendBuffer fully after the appendwindow.