These variables could be used from any gypi file included from chrome.gyp.
However, policy_templates.gypi is moving into components/policy.gypi, which
is included from components/components.gyp instead.
Moving the variables to build/chrome_settings.gypi enables their use from other gyp files.
BUG=271392
Review URL: https://codereview.chromium.org/98363007
git-svn-id: http://src.chromium.org/svn/trunk/src/build@240367 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
joaodasilva@chromium.org