Revert "Revert 143261 - Upstreaming android tools"

build/android/cmd_helper.py

-# Copyright (c) 2011 The Chromium Authors. All rights reserved.
+#!/usr/bin/python
+#
+# Copyright (c) 2012 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.
 
+"""A wrapper for subprocess to make calling shell commands easier."""
+
 
 import logging
 import subprocess
 
 
 def RunCmd(args, cwd=None):
   """Opens a subprocess to execute a program and returns its return value.
 
   Args:
     args: A string or a sequence of program arguments. The program to execute is
       the string or the first item in the args sequence.
     cwd: If not None, the subprocess's current directory will be changed to
       |cwd| before it's executed.
+
+  Returns:
+    Return code from the command execution.
   """
   logging.info(str(args) + ' ' + (cwd or ''))
   p = subprocess.Popen(args=args, cwd=cwd)
   return p.wait()
 
 
-def GetCmdOutput(args, cwd=None):
+def GetCmdOutput(args, cwd=None, shell=False):
   """Open a subprocess to execute a program and returns its output.
 
   Args:
     args: A string or a sequence of program arguments. The program to execute is
       the string or the first item in the args sequence.
     cwd: If not None, the subprocess's current directory will be changed to
       |cwd| before it's executed.
+    shell: Whether to execute args as a shell command.
+
+  Returns:
+    Captures and returns the command's stdout.
+    Prints the command's stderr to logger (which defaults to stdout).
   """
   logging.info(str(args) + ' ' + (cwd or ''))
   p = subprocess.Popen(args=args, cwd=cwd, stdout=subprocess.PIPE,
-                       stderr=subprocess.PIPE)
+                       stderr=subprocess.PIPE, shell=shell)
   stdout, stderr = p.communicate()
   if stderr:
     logging.critical(stderr)
   logging.info(stdout[:4096])  # Truncate output longer than 4k.
   return stdout