add touchpad-tests into autotest-deps

BUG=chromium-os:37644
TEST=emerge-link autotest-deps should build successfully and setup
  touchpad-tests under
  /build/link/usr/local/autotest/client/deps/touchpad-tests

Change-Id: I97a2fb544423d590df718cf50e9af390f98e2d96
Signed-off-by: Chung-yih Wang <cywang@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/44146
Reviewed-by: Joseph Shyh-In Hwang <josephsih@chromium.org>
diff --git a/client/deps/touchpad-tests/common.py b/client/deps/touchpad-tests/common.py
new file mode 100644
index 0000000..1f200aa
--- /dev/null
+++ b/client/deps/touchpad-tests/common.py
@@ -0,0 +1,15 @@
+# Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# This is a common boiler-plate module that is used to set up autotest_lib into
+# the PYTHONPATH. It should be copied into every deps directory.
+
+import os, sys
+dirname = os.path.dirname(sys.modules[__name__].__file__)
+client_dir = os.path.abspath(os.path.join(dirname, "..", ".."))
+sys.path.insert(0, client_dir)
+import setup_modules
+sys.path.pop(0)
+setup_modules.setup(base_path=client_dir,
+                    root_module_name="autotest_lib.client")