shill: Cellular device: GetModemStatus and GetModemInfo.

Also, put in place the skeleton for all Start/Enable steps.

BUG=chromium-os:18315
TEST=unit tests, tested on device

Change-Id: If8b5a8ba9bbcfa99f1c6b168bd8307c1578155f7
Reviewed-on: http://gerrit.chromium.org/gerrit/5082
Tested-by: Darin Petkov <petkov@chromium.org>
Reviewed-by: Jason Glasgow <jglasgow@chromium.org>
Reviewed-by: Chris Masone <cmasone@chromium.org>
diff --git a/mock_modem_proxy.h b/mock_modem_proxy.h
index 7146ede..e203433 100644
--- a/mock_modem_proxy.h
+++ b/mock_modem_proxy.h
@@ -14,6 +14,7 @@
 class MockModemProxy : public ModemProxyInterface {
  public:
   MOCK_METHOD1(Enable, void(const bool enable));
+  MOCK_METHOD0(GetInfo, Info());
 };
 
 }  // namespace shill