Fix a regression introduced in r77997.

An error message would be printed at each update_depot_tools invocation.

TBR=mhm
BUG=none
TEST=running gclient shouldn't print an error message at each invocation anymore

Review URL: http://codereview.chromium.org/6690008

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@78021 0039d316-1c4b-4281-b951-d872f2087c98

update_depot_tools

@@ -40,7 +40,7 @@ function test_git_svn {
 
 # Get the current SVN revision.
 get_svn_revision() {
-  echo `svn info | awk '{ if ($1 == "Revision:") { print $2 }}'`
+  echo `svn info "$base_dir" | awk '{ if ($1 == "Revision:") { print $2 }}'`
 }
 
 # Update git checkouts prior the cygwin check, we don't want to use msysgit.