Fix checkout root detection for git.

Add shorthand parameters.

Stop changing the logging level in gcl and some logging changes.

Change SCM.GetCheckoutRoot() to SCM.checkout_root.

TEST=none
BUG=none

Review URL: http://codereview.chromium.org/523094

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@35683 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/gclient_utils.py b/gclient_utils.py
index b83f8c9..5068563 100644
--- a/gclient_utils.py
+++ b/gclient_utils.py
@@ -41,7 +41,7 @@
 
   Works on python 2.4
   """
-  logging.debug(command)
+  logging.debug("%s, cwd=%s" % (str(command), str(cwd)))
   try:
     stderr = None
     if not print_error:
@@ -52,7 +52,7 @@
                                stderr=stderr)
     output = process.communicate()[0]
   except OSError, e:
-    raise CheckCallError(command, cwd, errno, None)
+    raise CheckCallError(command, cwd, e.errno, None)
   if process.returncode:
     raise CheckCallError(command, cwd, process.returncode, output)
   return output