Separate the posix part of the c-ares driver
diff --git a/config.m4 b/config.m4
index 8190485..a5b041f 100644
--- a/config.m4
+++ b/config.m4
@@ -370,6 +370,7 @@
     src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.cc \
     src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc \
     src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc \
+    src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc \
     src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc \
     src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc \
     src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc \