add NewGitCheckout to git_utils.py

add NewGitCheckout to git_utils.py

rebaseline_server will use this to check out expectations at specific revisions

BUG=skia:1918
TBR=rmistry

Committed: https://skia.googlesource.com/common/+/a7b0283

[epoger, 2014-08-13 19:07:33]

Ravi, PTAL at patchset 2.

(Patchset 1 just copied over what I originally had in the other CL; patchset 2
addresses your comments from the original CL)

[epoger, 2014-08-13 19:16:19]

committing TBR

[epoger, 2014-08-13 19:16:32]

The CQ bit was checked by epoger@google.com

[epoger, 2014-08-13 19:16:51]

The CQ bit was unchecked by epoger@google.com

[epoger, 2014-08-13 19:17:10]

Committed patchset #3 manually as a7b0283 (presubmit successful).

[rmistry, 2014-08-13 20:13:20]

LGTM

https://codereview.chromium.org/464413003/diff/30003/py/utils/git_utils.py
File py/utils/git_utils.py (right):

https://codereview.chromium.org/464413003/diff/30003/py/utils/git_utils.py#ne...
py/utils/git_utils.py:156: containing_dir=None):
I think it makes sense to have this default to tempfile.gettempdir() and to
update documentation saying that the platform specific tmp dir is the default
containing dir.

[rmistry, 2014-08-13 20:14:20]

https://codereview.chromium.org/464413003/diff/30003/py/utils/git_utils.py
File py/utils/git_utils.py (right):

https://codereview.chromium.org/464413003/diff/30003/py/utils/git_utils.py#ne...
py/utils/git_utils.py:156: containing_dir=None):
On 2014/08/13 20:13:20, rmistry wrote:
> I think it makes sense to have this default to tempfile.gettempdir() and to
> update documentation saying that the platform specific tmp dir is the default
> containing dir.

Ah I just saw your documentation update, so if dir=None then it automatically
defaults to platform specific tmp dir? if so then please ignore my last comment.

[epoger, 2014-08-13 21:03:45]

https://codereview.chromium.org/464413003/diff/30003/py/utils/git_utils.py
File py/utils/git_utils.py (right):

https://codereview.chromium.org/464413003/diff/30003/py/utils/git_utils.py#ne...
py/utils/git_utils.py:156: containing_dir=None):
On 2014/08/13 20:14:20, rmistry wrote:
> On 2014/08/13 20:13:20, rmistry wrote:
> > I think it makes sense to have this default to tempfile.gettempdir() and to
> > update documentation saying that the platform specific tmp dir is the
default
> > containing dir.
> 
> Ah I just saw your documentation update, so if dir=None then it automatically
> defaults to platform specific tmp dir? if so then please ignore my last
comment.

Yup, you got it.