PM: Make the connection type an enum class.

This improves type safety and encapsulation, but otherwise a superficial
syntactic substitution.

BUG=None
TEST=Unit tests.

Change-Id: I0ec880833704227cf6277ff37e37b51f8a8c5ce7
Reviewed-on: https://chromium-review.googlesource.com/189852
Reviewed-by: Gilad Arnold <garnold@chromium.org>
Commit-Queue: Gilad Arnold <garnold@chromium.org>
Tested-by: Gilad Arnold <garnold@chromium.org>
diff --git a/policy_manager/fake_shill_provider.h b/policy_manager/fake_shill_provider.h
index acc14f3..8919d16 100644
--- a/policy_manager/fake_shill_provider.h
+++ b/policy_manager/fake_shill_provider.h
@@ -20,7 +20,7 @@
     set_var_is_connected(
         new FakeVariable<bool>("is_connected", kVariableModePoll));
     set_var_conn_type(
-        new FakeVariable<ShillConnType>("conn_type", kVariableModePoll));
+        new FakeVariable<ConnectionType>("conn_type", kVariableModePoll));
     set_var_conn_last_changed(
         new FakeVariable<base::Time>("conn_last_changed", kVariableModePoll));
     return true;