[DevTools] Tracing handler keeps running even after devtools frontend has been closed.

content/browser/devtools/devtools_tracing_handler.cc

 // 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.
 
 #include "content/browser/devtools/devtools_tracing_handler.h"
 
 #include <cmath>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 182 matching lines @@
 
 void DevToolsTracingHandler::OnBufferUsage(float usage) {
   base::DictionaryValue* params = new base::DictionaryValue();
   params->SetDouble(devtools::Tracing::bufferUsage::kParamValue, usage);
   SendNotification(devtools::Tracing::bufferUsage::kName, params);
 }
 
 scoped_refptr<DevToolsProtocol::Response>
 DevToolsTracingHandler::OnEnd(
     scoped_refptr<DevToolsProtocol::Command> command) {
-  buffer_usage_poll_timer_.reset();
-  TracingController::GetInstance()->DisableRecording(
-      base::FilePath(),
+  DisableRecording(
       base::Bind(&DevToolsTracingHandler::BeginReadingRecordingResult,
                  weak_factory_.GetWeakPtr()));
   return command->SuccessResponse(NULL);
 }
 
+void DevToolsTracingHandler::DisableRecording(
+    const TracingController::TracingFileResultCallback& callback) {
+  buffer_usage_poll_timer_.reset();
+  TracingController::GetInstance()->DisableRecording(base::FilePath(),
+                                                     callback);
+}
+
+void DevToolsTracingHandler::OnClientDetached() {
+    DisableRecording();
+}
+
 }  // namespace content