devserver: start using payload scripts bundled with devserver

buildutil.py

Index: buildutil.py
diff --git a/buildutil.py b/buildutil.py
index 2447b2ce28ebc3bee5f442face7961cf1ee6048e..6b31f8ecbfb54512faac3ce62a716ea8c47ff25f 100644
--- a/buildutil.py
+++ b/buildutil.py
@@ -2,6 +2,8 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import os, sys
+
 class BuildObject(object):
   """
     Common base class that defines key paths in the source tree.
@@ -9,7 +11,8 @@ class BuildObject(object):
   def __init__(self, root_dir, static_dir):
     self.app_id = "87efface-864d-49a5-9bb3-4b050a7c227a"
     self.root_dir = root_dir
-    self.scripts_dir = "%s/scripts" % self.root_dir
+    self.scripts_dir = "%s/src/scripts" % os.environ["CROS_WORKON_SRCROOT"]
+    self.devserver_dir = os.path.dirname(os.path.abspath(sys.argv[0]))
     self.static_dir = static_dir
     self.x86_pkg_dir = "%s/build/x86/local_packages" % self.root_dir