In preparation for some Windows optimizations to how git_common calls
git it is important to use git_common more widely, specifically from
scm.py and gclient_scm.py. This change updates scm.py and gclient_scm.py
and updates the associated tests:
Test command lines used when updating the tests include:
vpython3 tests/gclient_scm_test.py ManagedGitWrapperTestCaseMock.testUpdateConflict
vpython3 tests/gclient_scm_test.py GerritChangesTest.testRecoversAfterPatchFailure
vpython3 tests/gerrit_util_test.py CookiesAuthenticatorTest.testGetGitcookiesPath
Bug: 332982922
Change-Id: I7aacb110b2888c164259815385cd77e26942adc7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/5478509
Commit-Queue: Bruce Dawson <brucedawson@chromium.org>
Reviewed-by: Gavin Mak <gavinmak@google.com>