Correctly pass the issue number as "issue" parameter to Changelist ctor

Instead of as branchref. Because it's an issue. Not a branchref.

Also, add myself as owner.

BUG=none
R=maruel@chromium.org

Review URL: https://chromiumcodereview.appspot.com/19997004

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@213387 0039d316-1c4b-4281-b951-d872f2087c98

OWNERS

@@ -3,6 +3,7 @@ bradnelson@google.com
 cmp@chromium.org
 dpranke@chromium.org
 iannucci@chromium.org
+jochen@chromium.org
 maruel@chromium.org
 maruel@google.com
 petermayo@chromium.org

git_cl.py

@@ -1795,7 +1795,7 @@ def CMDpatch(parser, args):
   if issue_arg.isdigit():
     # Input is an issue id.  Figure out the URL.
     issue = int(issue_arg)
-    cl = Changelist(issue)
+    cl = Changelist(issue=issue)
     patchset = cl.GetMostRecentPatchset()
     patch_data = cl.GetPatchSetDiff(issue, patchset)
   else: