Pass -S option to wrapper for python binary.

Prevent problem for some users using PAR file built by android's
build system which cause by the different site package of python
installed by user themselves.

Bug: 120469915
Test: 1. m atest
         atest --help
      2. apply aosp/861470
         full build

Change-Id: I72c83f9397f0e88eecfcd32806f1746520299447

python/scripts/stub_template_host.txt

@@ -12,6 +12,9 @@ PYTHON_BINARY = '%interpreter%'
 MAIN_FILE = '%main%'
 PYTHON_PATH = 'PYTHONPATH'
 
+# Don't imply 'import site' on initialization
+PYTHON_ARG = '-S'
+
 def SearchPathEnv(name):
   search_path = os.getenv('PATH', os.defpath).split(os.pathsep)
   for directory in search_path:
@@ -73,7 +76,7 @@ def Main():
     python_program = FindPythonBinary()
     if python_program is None:
       raise AssertionError('Could not find python binary: ' + PYTHON_BINARY)
-    args = [python_program, main_filepath] + args
+    args = [python_program, PYTHON_ARG, main_filepath] + args
 
     os.environ.update(new_env)