Make subprocess2.check_call() compliant with subprocess.check_call().

Rename check_call to check_call_out. It's a quite specific need when stderr is
needed or when the user doesn't want the default arguments of check_output.

R=dpranke@chromium.org
BUG=
TEST=

Review URL: http://codereview.chromium.org/6882127

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@83023 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/subprocess2.py b/subprocess2.py
index acfe4a9..4ba3c65 100644
--- a/subprocess2.py
+++ b/subprocess2.py
@@ -256,7 +256,7 @@
   return communicate(args, **kwargs)[1]
 
 
-def check_call(args, **kwargs):
+def check_call_out(args, **kwargs):
   """Improved version of subprocess.check_call().
 
   Returns (stdout, stderr), unlike subprocess.check_call().
@@ -268,6 +268,12 @@
   return out
 
 
+def check_call(args, **kwargs):
+  """Emulate subprocess.check_call()."""
+  check_call_out(args, **kwargs)
+  return 0
+
+
 def capture(args, **kwargs):
   """Captures stdout of a process call and returns it.
 
@@ -287,9 +293,9 @@
 
 
 def check_output(args, **kwargs):
-  """Captures stdout of a process call and returns it.
+  """Emulates subprocess.check_output().
 
-  Returns stdout.
+  Captures stdout of a process call and returns stdout only.
 
   - Discards stderr. By default sets stderr=STDOUT.
   - Throws if return code is not 0.
@@ -302,4 +308,4 @@
     kwargs['stdout'] = PIPE
   if kwargs.get('stderr') is None:
     kwargs['stderr'] = STDOUT
-  return check_call(args, **kwargs)[0]
+  return check_call_out(args, **kwargs)[0]