Fix bug in git cl patch using raw patch URL.

Fix bug in git cl patch using raw patch URL.

When using a raw URL from a different Rietveld instance than the one
in codereview.settings, you get an error like this:

File "depot_tools/git_cl.py", line 2767, in PatchIssue
    RunGit(['commit', '-m', (cl.GetDescription() + '\n\n' +
UnboundLocalError: local variable 'cl' referenced before assignment

This fixes that. It is needed for the WebRTC transition to the
Chromium Rietveld instance using https://codereview.webrtc.org

BUG=webrtc:3884
TESTED=In a WebRTC checkout: ran 'git cl patch https://codereview.webrtc.org/download/issue1135893005_1.diff'
on a clean branch and had it apply correctly.
In a Chromium checkout, ran 'git cl patch 1154023002' and verified
the commit message was correct.
I also ran using the raw URL and verified the result was the same.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=295491

[kjellander_chromium, 2015-06-01 11:48:18]

kjellander@chromium.org changed reviewers:
+ agable@chromium.org

[agable, 2015-06-01 21:22:54]

https://codereview.chromium.org/1166673002/diff/1/git_cl.py
File git_cl.py (right):

https://codereview.chromium.org/1166673002/diff/1/git_cl.py#newcode2768
git_cl.py:2768: commit_message = cl.GetDescription() + '\n\n' if arg_is_issue_id
else ''
Rather than removing functionality (replacing the description with the
emptystring), instead create a cl = Changelist(...) in the else: clause above,
and explicitly set cl.rietveld_server to be the right thing. Then this call
should work.

[kjellander_chromium, 2015-06-02 07:47:10]

https://codereview.chromium.org/1166673002/diff/1/git_cl.py
File git_cl.py (right):

https://codereview.chromium.org/1166673002/diff/1/git_cl.py#newcode2768
git_cl.py:2768: commit_message = cl.GetDescription() + '\n\n' if arg_is_issue_id
else ''
On 2015/06/01 21:22:53, agable wrote:
> Rather than removing functionality (replacing the description with the
> emptystring), instead create a cl = Changelist(...) in the else: clause above,
> and explicitly set cl.rietveld_server to be the right thing. Then this call
> should work.

Good idea. That was pretty simple to do by just updating the regexp.

[agable, 2015-06-02 17:39:29]

lgtm

[kjellander_chromium, 2015-06-02 18:31:54]

The CQ bit was checked by kjellander@chromium.org

[commit-bot: I haz the power, 2015-06-02 18:32:37]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1166673002/20001

[commit-bot: I haz the power, 2015-06-02 18:35:32]

Committed patchset #2 (id:20001) as
http://src.chromium.org/viewvc/chrome?view=rev&revision=295491