GitLab

- switches::kGoogleBaseURL is moved into the Google component

- The information of whether background networking is enabled is now obtained
  from GoogleURLTrackerClient.

BUG=373222
TBR=thakis

Review URL: https://codereview.chromium.org/301383003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@274143 0039d316-1c4b-4281-b951-d872f2087c98