Revert 237280 "Remove TraceController"

trunk/src/chrome/browser/feedback/tracing_manager.h

 // Copyright 2013 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 CHROME_BROWSER_FEEDBACK_TRACING_MANAGER_H_
 #define CHROME_BROWSER_FEEDBACK_TRACING_MANAGER_H_
 
 #include <map>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
+#include "content/public/browser/trace_subscriber.h"
 
-namespace base {
-
-class RefCountedString;
-class FilePath;
-
-}
 // Callback used for getting the output of a trace.
 typedef base::Callback<void(scoped_refptr<base::RefCountedString> trace_data)>
     TraceDataCallback;
 
-// This class is used to manage performance metrics that can be attached to
+// This class is used to manage performance meterics that can be attached to
 // feedback reports.  This class is a Singleton that is owned by the preference
 // system.  It should only be created when it is enabled, and should only be
 // accessed elsewhere via Get().
 //
 // When a performance trace is desired, TracingManager::Get()->RequestTrace()
 // should be invoked.  The TracingManager will then start preparing a zipped
 // version of the performance data.  That data can then be requested via
 // GetTraceData().  When the data is no longer needed, it should be discarded
 // via DiscardTraceData().
-class TracingManager {
+class TracingManager : public content::TraceSubscriber {
  public:
   virtual ~TracingManager();
 
   // Create a TracingManager.  Can only be called when none exists.
   static scoped_ptr<TracingManager> Create();
 
   // Get the current TracingManager.  Returns NULL if one doesn't exist.
   static TracingManager* Get();
 
   // Request a trace ending at the current time.  If a trace is already being
   // collected, the id for that trace is returned.
   int RequestTrace();
 
   // Get the trace data for |id|.  On success, true is returned, and the data is
   // returned via |callback|.  Returns false on failure.
   bool GetTraceData(int id, const TraceDataCallback& callback);
 
   // Discard the data for trace |id|.
   void DiscardTraceData(int id);
 
  private:
+  void StartTracing();
+
+  // content::TraceSubscriber overrides
+  virtual void OnEndTracingComplete() OVERRIDE;
+  virtual void OnTraceDataCollected(
+      const scoped_refptr<base::RefCountedString>& trace_fragment) OVERRIDE;
+
   TracingManager();
 
-  void StartTracing();
-  void OnTraceDataCollected(const base::FilePath& path);
+  // Data being collected from the current trace.
+  std::string data_;
 
   // ID of the trace that is being collected.
   int current_trace_id_;
 
   // Mapping of trace ID to trace data.
   std::map<int, scoped_refptr<base::RefCountedString> > trace_data_;
 
   // Callback for the current trace request.
   TraceDataCallback trace_callback_;
 
   base::WeakPtrFactory<TracingManager> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(TracingManager);
 };
 
 #endif  // CHROME_BROWSER_FEEDBACK_TRACING_MANAGER_H_