Migrate DBus service constants from flimflam namespace to shill namespace.

All shill DBus service constants have been moved from the flimflam namespace to
the shill namespace. This CL makes the corresponding changes on the Chrome
side.

Related CLs:
  https://chromium-review.googlesource.com/#/c/170123/
  https://chromium-review.googlesource.com/#/c/170205/
  https://chromium-review.googlesource.com/#/c/170206/
  https://chromium-review.googlesource.com/#/c/170207/
  https://chromium-review.googlesource.com/#/c/170208/
  https://chromium-review.googlesource.com/#/c/170209/
  https://chromium-review.googlesource.com/#/c/170223/
  https://chromium-review.googlesource.com/#/c/170230/
  https://chromium-review.googlesource.com/#/c/170231/

BUG=295425
R=dbeam@chromium.org, stevenjb@chromium.org

Review URL: https://codereview.chromium.org/24331008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225151 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225151