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

base/trace_event/heap_profiler_stack_frame_deduplicator.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/trace_event/heap_profiler_stack_frame_deduplicator.h"
 
 #include <inttypes.h>
 #include <stddef.h>
 
 #include <string>
 #include <utility>
 
 #include "base/strings/stringprintf.h"
 #include "base/trace_event/heap_profiler_string_deduplicator.h"
 #include "base/trace_event/memory_usage_estimator.h"
+#include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "base/trace_event/trace_event_memory_overhead.h"
 
 namespace base {
 namespace trace_event {
 
 StackFrameDeduplicator::FrameNode::FrameNode(StackFrame frame,
                                              int parent_frame_index)
     : frame(frame), parent_frame_index(parent_frame_index) {}
 StackFrameDeduplicator::FrameNode::FrameNode(const FrameNode& other) = default;
@@ skipping 47 matching lines @@
       frame_index = node->second;
     }
 
     nodes = &frames_[frame_index].children;
   }
 
   return frame_index;
 }
 
 void StackFrameDeduplicator::SerializeIncrementally(TracedValue* traced_value) {
+  TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("memory-infra"),
+               "StackFrameDeduplicator::SerializeIncrementally");
   std::string stringify_buffer;
 
   for (; last_exported_index_ < frames_.size(); ++last_exported_index_) {
     const auto& frame_node = frames_[last_exported_index_];
     traced_value->BeginDictionary();
 
     traced_value->SetInteger("id", last_exported_index_);
 
     int name_string_id = 0;
     const StackFrame& frame = frame_node.frame;
@@ skipping 28 matching lines @@
 void StackFrameDeduplicator::EstimateTraceMemoryOverhead(
     TraceEventMemoryOverhead* overhead) {
   size_t memory_usage =
       EstimateMemoryUsage(frames_) + EstimateMemoryUsage(roots_);
   overhead->Add(TraceEventMemoryOverhead::kHeapProfilerStackFrameDeduplicator,
                 sizeof(StackFrameDeduplicator) + memory_usage);
 }
 
 }  // namespace trace_event
 }  // namespace base