Revert "Make gclient fetch git repos recursively. This is needed when adding a git repo through DEPS. If that repo has submodules, we need to fetch them or else the repo won't be complete."

This reverts commit 6a2e4710.

cmp says:
This CL causes NewGit and Git submodules workflows to comingle in ways that result in bad and unexpected failures for new and existing users.  One failure is for the new Blink developers who need to use git-svn with their WebKit third_party checkout.  Another failure is in the Windows NewGit workflow where gclient sync takes longer than necessary to complete.

The right approach at this point given the costs of this change is to revert it and rethink the best way to get projects the functionality they need while restoring the functionality existing projects have required for over a year now.

Please discuss the recursive/recurseSubmodules code face-to-face with cmp@google.com before attempting to make this live again.  Thanks.

R=cmp@chromium.org
BUG=224074


Review URL: https://chromiumcodereview.appspot.com/13470027

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@192236 0039d316-1c4b-4281-b951-d872f2087c98