[tracing] Add trace events to key heap profiler functions.

base/trace_event/heap_profiler_type_name_deduplicator.cc

Index: base/trace_event/heap_profiler_type_name_deduplicator.cc
diff --git a/base/trace_event/heap_profiler_type_name_deduplicator.cc b/base/trace_event/heap_profiler_type_name_deduplicator.cc
index 0f011653b1ea0d735f2e562e2a324ff599d931eb..8224b5a9cfa92f7aa6869b99fa967112edb9e71b 100644
--- a/base/trace_event/heap_profiler_type_name_deduplicator.cc
+++ b/base/trace_event/heap_profiler_type_name_deduplicator.cc
@@ -87,6 +87,8 @@ int TypeNameDeduplicator::Insert(const char* type_name) {
 }
 
 void TypeNameDeduplicator::SerializeIncrementally(TracedValue* traced_value) {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("memory-infra"),
+               "TypeNameDeduplicator::SerializeIncrementally");
   for (const auto* name_and_id : new_type_ids_) {
     traced_value->BeginDictionary();