Randomly enable leak detector based on probability parameter

chrome/renderer/leak_detector/leak_detector_remote_client.h

 // Copyright 2016 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_RENDERER_LEAK_DETECTOR_LEAK_DETECTOR_REMOTE_CLIENT_H_
 #define CHROME_RENDERER_LEAK_DETECTOR_LEAK_DETECTOR_REMOTE_CLIENT_H_
 
 #include "base/macros.h"
 #include "components/metrics/leak_detector/leak_detector.h"
 #include "components/metrics/leak_detector/leak_detector.mojom.h"
+#include "content/public/renderer/render_thread_observer.h"
 
-class LeakDetectorRemoteClient : public metrics::LeakDetector::Observer {
+class LeakDetectorRemoteClient : public content::RenderThreadObserver,
+                                 public metrics::LeakDetector::Observer {
  public:
   LeakDetectorRemoteClient();
   ~LeakDetectorRemoteClient() override;
 
   // metrics::LeakDetector::Observer:
   void OnLeaksFound(
       const std::vector<metrics::MemoryLeakReportProto>& reports) override;
 
  private:
+  // contents::RenderThreadObserver:
+  void OnRenderProcessShutdown() override;
+
   // Callback for remote function LeakDetectorRemote::GetParams().
   void OnParamsReceived(
       mojo::StructPtr<metrics::mojom::LeakDetectorParams> result);
 
   // Handle to the remote Mojo interface.
   metrics::mojom::LeakDetectorPtr remote_service_;
 
   DISALLOW_COPY_AND_ASSIGN(LeakDetectorRemoteClient);
 };
 
 #endif  // CHROME_RENDERER_LEAK_DETECTOR_LEAK_DETECTOR_REMOTE_CLIENT_H_