[shill] Start replacing bare pointers with scoped_refptrs where appropriate

BUG=chromium-os:16259
TEST=unit tests

Change-Id: I5e1531b726bbb40917d25dc3ae44da9a6a420e00
Reviewed-on: http://gerrit.chromium.org/gerrit/2236
Tested-by: Chris Masone <cmasone@chromium.org>
Reviewed-by: Darin Petkov <petkov@chromium.org>
27 files changed