use inheritance instead of composition so TraceMeProducer/Consumer can call AppendMetadta.

PiperOrigin-RevId: 501886665

Author: trisolaran

tsl/profiler/lib/connected_traceme.h

@@ -74,17 +74,17 @@ namespace profiler {
  * // context_id is passed from the producer thread.
  * TraceMeConsumer consumer([&] { return "op_execute"; }, context_id);
  */
-class TraceMeProducer {
+class TraceMeProducer : public TraceMe {
  public:
   template <typename NameT>
   explicit TraceMeProducer(NameT&& name,
                            ContextType context_type = ContextType::kGeneric,
                            absl::optional<uint64> context_id = absl::nullopt,
                            int level = 2)
-      : context_id_(context_id.has_value() ? context_id.value()
-                                           : TraceMe::NewActivityId()),
-        trace_me_(std::forward<NameT>(name), level) {
-    trace_me_.AppendMetadata([&] {
+      : TraceMe(std::forward<NameT>(name), level),
+        context_id_(context_id.has_value() ? context_id.value()
+                                           : TraceMe::NewActivityId()) {
+    AppendMetadata([&] {
       return TraceMeEncode({{"_pt", context_type}, {"_p", context_id_}});
     });
   }
@@ -93,16 +93,15 @@ class TraceMeProducer {
 
  private:
   uint64 context_id_;
-  TraceMe trace_me_;
 };
 
-class TraceMeConsumer {
+class TraceMeConsumer : public TraceMe {
  public:
   template <typename NameT>
   TraceMeConsumer(NameT&& name, ContextType context_type, uint64 context_id,
                   int level = 2)
-      : trace_me_(std::forward<NameT>(name), level) {
-    trace_me_.AppendMetadata([&] {
+      : TraceMe(std::forward<NameT>(name), level) {
+    AppendMetadata([&] {
       return TraceMeEncode({{"_ct", context_type}, {"_c", context_id}});
     });
   }
@@ -111,9 +110,6 @@ class TraceMeConsumer {
   TraceMeConsumer(NameT&& name, uint64 context_id, int level = 2)
       : TraceMeConsumer(std::forward<NameT>(name), ContextType::kGeneric,
                         context_id, level) {}
-
- private:
-  TraceMe trace_me_;
 };
 
 }  // namespace profiler