Add a new script bb_host_steps.py which handles all host side steps.

build/android/buildbot/bb_utils.py

Index: build/android/buildbot/bb_utils.py
diff --git a/build/android/buildbot/bb_utils.py b/build/android/buildbot/bb_utils.py
new file mode 100644
index 0000000000000000000000000000000000000000..8dd9f9a0a32aaee2e4cf2e6411d04de36bb7bf4e
--- /dev/null
+++ b/build/android/buildbot/bb_utils.py
@@ -0,0 +1,77 @@
+# 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.
+
+import json
+import optparse
+import os
+import pipes
+import subprocess
+import sys
+
+sys.path.append(os.path.join(os.path.dirname(__file__), '..'))
+from pylib import buildbot_report
+from pylib import constants
+
+
+TESTING = 'BUILDBOT_TESTING' in os.environ
+
+BB_BUILD_DIR = os.path.abspath(
+    os.path.join(os.path.dirname(__file__), os.pardir, os.pardir, os.pardir,
+    os.pardir, os.pardir, os.pardir, os.pardir))
+
+
+def SpawnCmd(command):
+  """Spawn a process without waiting for termination."""
+  print '>', ' '.join(map(pipes.quote, command))

[Isaac (away), 2013/06/06 21:26:46]

use commandtostring()

[Siva Chandra, 2013/06/06 22:10:47]

Done.

+  sys.stdout.flush()
+  if TESTING:
+    class MockPopen(object):
+      @staticmethod
+      def wait():
+        return 0
+    return MockPopen()
+
+  return subprocess.Popen(command, cwd=constants.CHROME_DIR)
+
+
+def RunCmd(command, flunk_on_failure=True, halt_on_failure=False,
+           warning_code=88):
+  """Run a command relative to the chrome source root."""
+  code = SpawnCmd(command).wait()
+  print '<', ' '.join(map(pipes.quote, command))

[Isaac (away), 2013/06/06 21:26:46]

use commandtostring()

[Siva Chandra, 2013/06/06 22:10:47]

Done.

+  if code != 0:
+    print 'ERROR: process exited with code %d' % code
+    if flunk_on_failure and code != warning_code:
+      buildbot_report.PrintError()
+    else:
+      buildbot_report.PrintWarning()
+    # Allow steps to have both halting (i.e. 1) and non-halting exit codes.
+    if code != 0 and code != 88 and halt_on_failure:

[Isaac (away), 2013/06/06 21:26:46]

can you change this line to 
if code != warning_code and half_on_failure:

[Siva Chandra, 2013/06/06 22:10:47]

Done.

+      raise OSError()
+  return code
+
+
+def ConvertJson(option, _, value, parser):

[Isaac (away), 2013/06/06 21:26:46]

nit, would be little cleaner to make this an inner function inside GetParser

[Siva Chandra, 2013/06/06 22:10:47]

Done.

+  setattr(parser.values, option.dest, json.loads(value))
+
+
+def GetParser():
+  parser = optparse.OptionParser()
+  parser.add_option('--build-properties', action='callback',
+                    callback=ConvertJson, type='string', default={},
+                    help='build properties in JSON format')
+  parser.add_option('--factory-properties', action='callback',
+                    callback=ConvertJson, type='string', default={},
+                    help='factory properties in JSON format')
+  parser.add_option('--slave-properties', action='callback',
+                    callback=ConvertJson, type='string', default={},
+                    help='Properties set by slave script in JSON format')
+
+  return parser
+
+
+def CommandToString(command):

[Isaac (away), 2013/06/06 21:26:46]

nit, move this to the top since it's used by functions below

[Siva Chandra, 2013/06/06 22:10:47]

Done.

+  """Returns quoted command that can be run in bash shell."""
+  return ' '.join(map(pipes.quote, command))
+