initial commit of tracing context files
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 05aa323..221c132 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -479,6 +479,7 @@
   src/core/ext/census/operation.c
   src/core/ext/census/placeholders.c
   src/core/ext/census/resource.c
+  src/core/ext/census/trace_context.c
   src/core/ext/census/tracing.c
   src/core/plugin_registry/grpc_plugin_registry.c
 )
@@ -938,6 +939,7 @@
   src/core/ext/census/operation.c
   src/core/ext/census/placeholders.c
   src/core/ext/census/resource.c
+  src/core/ext/census/trace_context.c
   src/core/ext/census/tracing.c
   src/core/plugin_registry/grpc_unsecure_plugin_registry.c
 )