Addressing feedback.

include/grpc++/impl/codegen/client_context.h

@@ -309,9 +309,7 @@ class ClientContext {
 
   // Should be used for framework-level extensions only.
   // Applications never need to call this method.
-  grpc_call* c_call() const {
-    return call_;
-  }
+  grpc_call* c_call() { return call_; }
 
  private:
   // Disallow copy and assign.

include/grpc++/impl/codegen/server_context.h

@@ -168,9 +168,7 @@ class ServerContext {
 
   // Should be used for framework-level extensions only.
   // Applications never need to call this method.
-  grpc_call* c_call() const {
-    return call_;
-  }
+  grpc_call* c_call() { return call_; }
 
  private:
   friend class ::grpc::testing::InteropServerContextInspector;

src/core/lib/security/context/security_context.h

@@ -84,6 +84,11 @@ void grpc_auth_context_unref(grpc_auth_context *policy);
 
 void grpc_auth_property_reset(grpc_auth_property *property);
 
+/* --- grpc_security_context_extension ---
+
+   Extension to the security context that may be set in a filter and accessed
+   later by a higher level method on a grpc_call object. */
+
 typedef struct {
   void *instance;
   void (*destroy)(void *);