Cosmetic: Move logic from CommandListener into NetworkController.

CommandListener should just unmarshal params, and delegate all functional logic
to NetworkController (or other such classes). So, for example, if you call
destroyNetwork() directly from a unit test, you should get the same effect as if
you sent a "network destroy" command to CommandListener.

(cherry picked from commit f7743bf18672d654e79565e85c7d3770e2f0f26c)

Change-Id: Ic61ae9141e2eea95394a3a38e30a72fe964cdc81
diff --git a/NetworkController.cpp b/NetworkController.cpp
index eaaee5a..efa23f1 100644
--- a/NetworkController.cpp
+++ b/NetworkController.cpp
@@ -214,6 +214,10 @@
         setDefaultNetwork(NETID_UNSET);
     }
 
+// TODO: Uncomment once this API has been added to bionic.
+#if 0
+    _resolv_delete_cache_for_net(netId);
+#endif
     return status;
 }