Enable startup tracing from command line flags in components/tracing

base/trace_event/memory_dump_manager.h

 // 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.
 
 #ifndef BASE_TRACE_EVENT_MEMORY_DUMP_MANAGER_H_
 #define BASE_TRACE_EVENT_MEMORY_DUMP_MANAGER_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 99 matching lines @@
                          const MemoryDumpCallback& callback);
 
   // Same as above (still asynchronous), but without callback.
   void RequestGlobalDump(MemoryDumpType dump_type,
                          MemoryDumpLevelOfDetail level_of_detail);
 
   // TraceLog::EnabledStateObserver implementation.
   void OnTraceLogEnabled() override;
   void OnTraceLogDisabled() override;
 
+  // Enable heap profiling if kEnableHeapProfiling is specified.
+  void EnableHeapProfilingIfNeeded();
+
   // Returns true if the dump mode is allowed for current tracing session.
   bool IsDumpModeAllowed(MemoryDumpLevelOfDetail dump_mode);
 
   // Returns the MemoryDumpSessionState object, which is shared by all the
   // ProcessMemoryDump and MemoryAllocatorDump instances through all the tracing
   // session lifetime.
   const scoped_refptr<MemoryDumpSessionState>& session_state_for_testing()
       const {
     return session_state_;
   }
@@ skipping 172 matching lines @@
   static const int kMaxConsecutiveFailuresCount;
   static const char* const kSystemAllocatorPoolName;
 
   MemoryDumpManager();
   ~MemoryDumpManager() override;
 
   static void SetInstanceForTesting(MemoryDumpManager* instance);
   static void FinalizeDumpAndAddToTrace(
       std::unique_ptr<ProcessMemoryDumpAsyncState> pmd_async_state);
 
-  // Enable heap profiling if kEnableHeapProfiling is specified.
-  void EnableHeapProfilingIfNeeded();
-
   // Internal, used only by MemoryDumpManagerDelegate.
   // Creates a memory dump for the current process and appends it to the trace.
   // |callback| will be invoked asynchronously upon completion on the same
   // thread on which CreateProcessDump() was called.
   void CreateProcessDump(const MemoryDumpRequestArgs& args,
                          const MemoryDumpCallback& callback);
 
   // Calls InvokeOnMemoryDump() for the next MDP on the task runner specified by
   // the MDP while registration. On failure to do so, skips and continues to
   // next MDP.
@@ skipping 100 matching lines @@
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MemoryDumpManagerDelegate);
 };
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_MEMORY_DUMP_MANAGER_H_