Reland of [tracing] Add native allocation tracing mode.

base/trace_event/trace_event.h

 // Copyright (c) 2012 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.
 
 #ifndef BASE_TRACE_EVENT_TRACE_EVENT_H_
 #define BASE_TRACE_EVENT_TRACE_EVENT_H_
 
 // This header file defines implementation details of how the trace macros in
 // trace_event_common.h collect and store trace events. Anything not
 // implementation-specific should go in trace_event_common.h instead of here.
@@ skipping 1038 matching lines @@
  private:
   const char* previous_state_;
 };
 
 // ScopedTaskExecutionEvent records the current task's context in the heap
 // profiler.
 class ScopedTaskExecutionEvent {
  public:
   explicit ScopedTaskExecutionEvent(const char* task_context)
       : context_(task_context) {
+    using base::trace_event::AllocationContextTracker;
     if (UNLIKELY(
-            base::trace_event::AllocationContextTracker::capture_enabled())) {
-      base::trace_event::AllocationContextTracker::GetInstanceForCurrentThread()
+            AllocationContextTracker::capture_mode() !=
+            AllocationContextTracker::CaptureMode::DISABLED)) {
+      AllocationContextTracker::GetInstanceForCurrentThread()
           ->PushCurrentTaskContext(context_);
     }
   }
 
   ~ScopedTaskExecutionEvent() {
+    using base::trace_event::AllocationContextTracker;
     if (UNLIKELY(
-            base::trace_event::AllocationContextTracker::capture_enabled())) {
-      base::trace_event::AllocationContextTracker::GetInstanceForCurrentThread()
+            AllocationContextTracker::capture_mode() !=
+            AllocationContextTracker::CaptureMode::DISABLED)) {
+      AllocationContextTracker::GetInstanceForCurrentThread()
           ->PopCurrentTaskContext(context_);
     }
   }
 
  private:
   const char* context_;
 };
 
 }  // namespace trace_event_internal
 
@@ skipping 23 matching lines @@
   const char* name_;
   IDType id_;
 
   DISALLOW_COPY_AND_ASSIGN(TraceScopedTrackableObject);
 };
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_TRACE_EVENT_H_