Revert of Convert cpplint.py to work with nested git repositories. (patchset #1 id:1 of https://codereview.chromium.org/1897153003/ )

Reason for revert:
This breaks WebRTC presubmit on the buildbots (due to /b/build being a Git repo, which in turn contains the checkout). See  https://bugs.chromium.org/p/webrtc/issues/detail?id=5818 for more details.

It seems it also broke other projects (rakuco's comment #15).



Original issue's description:
> Convert cpplint.py to work with nested git repositories.
> 
> Chrome on iOS downstream repository tracks Chromium via DEPS and wants
> to use cpplint canned presubmit check but the cpplint.py errors due at
> the include guard as it stops at the inner most git repository.
> 
> Change cpplint.py to look for the outermost git repository when looking
> for the repository root.
> 
> BUG=598090
> 
> Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=300085

TBR=iannucci@chromium.org,skym@chromium.org,sdefresne@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=598090

Review URL: https://codereview.chromium.org/1919483002

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@300119 0039d316-1c4b-4281-b951-d872f2087c98