Also scan stderr for audio files to test, due to change in Android test_runner

webrtc/audio/test/low_bandwidth_audio_test.py

Index: webrtc/audio/test/low_bandwidth_audio_test.py
diff --git a/webrtc/audio/test/low_bandwidth_audio_test.py b/webrtc/audio/test/low_bandwidth_audio_test.py
index 3606e682224b0ce0606d6571a74aad90450969bb..abe9da9260677aef8cb478efb1441a09c7909493 100755
--- a/webrtc/audio/test/low_bandwidth_audio_test.py
+++ b/webrtc/audio/test/low_bandwidth_audio_test.py
@@ -198,7 +198,7 @@ def main():
     test_process = subprocess.Popen(
         _LogCommand(test_command + ['--sample_rate_hz=%d' %
                                     analyzer.sample_rate_hz]),
-        stdout=subprocess.PIPE)
+        stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
     try:
       lines = iter(test_process.stdout.readline, '')
       for result in ExtractTestRuns(lines, echo=True):