[autotest] chameleon: Fix pair_legacy_device argument for audio

pair_legacy_device syntax has been changed. Fix it by passing
trusted=False.

BUG=chromium:625777
TEST=run audio_AudioBasicBluetoothPlayback test and
audio_AudioBasicBluetoothPlaybackRecord test

Change-Id: I5a11923040b78dd97bdaaee22981a44cf182325e
Reviewed-on: https://chromium-review.googlesource.com/358283
Commit-Ready: Cheng-Yi Chiang <cychiang@chromium.org>
Tested-by: Cheng-Yi Chiang <cychiang@chromium.org>
Reviewed-by: Cheng-Yi Chiang <cychiang@chromium.org>
diff --git a/client/cros/chameleon/chameleon_bluetooth_audio.py b/client/cros/chameleon/chameleon_bluetooth_audio.py
index 39ca485..1e6b383 100644
--- a/client/cros/chameleon/chameleon_bluetooth_audio.py
+++ b/client/cros/chameleon/chameleon_bluetooth_audio.py
@@ -132,7 +132,7 @@
     # Pairs the bluetooth adapter with bluetooth module.
     for trial in xrange(retries):
         if bt_adapter.pair_legacy_device(
-            target_mac_address, pin, pairing_timeout):
+            target_mac_address, pin, False, pairing_timeout):
                 logging.debug('Pairing to %s succeeded', target_mac_address)
                 return
         elif trial == retries - 1: