Provision Android devices after the 'device_status_check' step.

build/android/host_heartbeat.py

Index: build/android/host_heartbeat.py
diff --git a/build/android/host_heartbeat.py b/build/android/host_heartbeat.py
new file mode 100755
index 0000000000000000000000000000000000000000..1449199618d957ba409e11d862d41edfbf65fbc5
--- /dev/null
+++ b/build/android/host_heartbeat.py
@@ -0,0 +1,34 @@
+#!/usr/bin/env python
+#
+# Copyright (c) 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Sends a heart beat pulse to the currently online Android devices.
+This heart beat lets the devices know that they are connected to a host.
+"""
+
+import os
+import sys
+import time
+
+from pylib import android_commands
+
+PULSE_PERIOD = 20
+
+def main():
+  while True:
+    try:
+      devices = android_commands.GetAttachedDevices()
+      for device in devices:
+        android_cmd = android_commands.AndroidCommands(device)
+        android_cmd.EnableAdbRoot()

[Isaac (away), 2013/03/28 22:37:44]

I don't think we should be called this here as it can disconnect adb.

Instead use 'su' as part of the command to run on phone as root.

[Siva Chandra, 2013/03/28 23:52:47]

If I add the 'su ' prefix, it says "permission denied". I removed
EnableAdbRoot() as the device should be on root anyway. The first part of the
provisioning script ensures this.

[Isaac (away), 2013/03/29 00:18:32]

You might not be calling with su right.  I think you need su -c and then putting
them command in another layer of quotes.

We should get this right because not all phones run as root.  I don't think the
perf ones do.

[Siva Chandra, 2013/03/29 01:47:06]

This is what I tried and tested to be working:

I dont put the phones on root. Just reboot them and run the provisioning script.
The adb_reboot binary is pushed and launched correctly. The host_heartbeat is
spawned and is touching the heartbeat file correctly.

What I have changed is the C code for the adb_reboot binary. I start and stop
adbd with su -c.

+        android_cmd.RunShellCommand('touch /sdcard/host_heartbeat')
+    except:
+      # Keep the heatbeat running bypassing all errors.
+      pass
+    time.sleep(PULSE_PERIOD)
+
+
+if __name__ == '__main__':
+  sys.exit(main())