Revert hard-coded src.git DEPS file name.
Revert hard-coded src.git DEPS file name.

This is breaking the ability to specify an alternate DEPS file, and do
things like sync release tags where DEPS is still from svn and we need
.DEPS.git to do a git checkout.

R=iannucci@chromium.org, szager@chromium.org
BUG=407049

Review URL: https://codereview.chromium.org/511533003

git-svn-id: bd64dd6fa6f3f0ed0c0666d1018379882b742947@291665 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

svn2github/chromium-depot-tools,svn2github/chromium-depot-tools,svn2github/chromium-depot-tools