Record Chrome trace events in tcmalloc heap profiles

base/debug/trace_event_impl.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_DEBUG_TRACE_EVENT_IMPL_H_
 #define BASE_DEBUG_TRACE_EVENT_IMPL_H_
 
 #include <stack>
 #include <string>
@@ skipping 326 matching lines @@
     // Called just after the tracing system becomes enabled, outside of the
     // |lock_|.  TraceLog::IsEnabled() is true at this point.
     virtual void OnTraceLogEnabled() = 0;
 
     // Called just after the tracing system disables, outside of the |lock_|.
     // TraceLog::IsEnabled() is false at this point.
     virtual void OnTraceLogDisabled() = 0;
   };
   void AddEnabledStateObserver(EnabledStateObserver* listener);
   void RemoveEnabledStateObserver(EnabledStateObserver* listener);
+  bool HasEnabledStateObserver(EnabledStateObserver* listener) const;
 
   float GetBufferPercentFull() const;
 
   // Set the thread-safe notification callback. The callback can occur at any
   // time and from any thread. WARNING: It is possible for the previously set
   // callback to be called during OR AFTER a call to SetNotificationCallback.
   // Therefore, the target of the callback must either be a global function,
   // ref-counted object or a LazyInstance with Leaky traits (or equivalent).
   typedef base::Callback<void(int)> NotificationCallback;
   void SetNotificationCallback(const NotificationCallback& cb);
@@ skipping 225 matching lines @@
 
   CategoryFilter category_filter_;
 
   DISALLOW_COPY_AND_ASSIGN(TraceLog);
 };
 
 }  // namespace debug
 }  // namespace base
 
 #endif  // BASE_DEBUG_TRACE_EVENT_IMPL_H_