gclient: Don't change directories when checking git version.

Review URL: http://codereview.chromium.org/495003

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@34392 0039d316-1c4b-4281-b951-d872f2087c98

gclient_scm.py

@@ -193,7 +193,7 @@ class GitWrapper(SCMWrapper, scm.GIT):
         return int(val)
       else:
         return 0
-    version = self._Run(['--version']).split()[-1]
+    version = self._Run(['--version'], cwd='.').split()[-1]
     version_list = map(only_int, version.split('.'))
     min_version_list = map(int, min_version.split('.'))
     for min_ver in min_version_list: