Move a file from src/cpp to src/core since core depends on it
diff --git a/CMakeLists.txt b/CMakeLists.txt
index c4526d2..32d7a9b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1239,7 +1239,7 @@
   src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_windows.cc
   src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.cc
   src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.cc
-  src/cpp/ext/filters/census/grpc_context.cc
+  src/core/ext/filters/census/grpc_context.cc
   src/core/ext/filters/max_age/max_age_filter.cc
   src/core/ext/filters/message_size/message_size_filter.cc
   src/core/ext/filters/http/client_authority_filter.cc
@@ -2560,7 +2560,7 @@
   third_party/nanopb/pb_encode.c
   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/cpp/ext/filters/census/grpc_context.cc
+  src/core/ext/filters/census/grpc_context.cc
   src/core/ext/filters/max_age/max_age_filter.cc
   src/core/ext/filters/message_size/message_size_filter.cc
   src/core/ext/filters/http/client_authority_filter.cc
@@ -3348,7 +3348,7 @@
   src/core/ext/transport/chttp2/server/insecure/server_chttp2.cc
   src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.cc
   src/core/ext/transport/chttp2/server/chttp2_server.cc
-  src/cpp/ext/filters/census/grpc_context.cc
+  src/core/ext/filters/census/grpc_context.cc
 )
 
 if(WIN32 AND MSVC)