[tracing] Add a memory dump provider for DOM storage

content/browser/dom_storage/dom_storage_task_runner.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 CONTENT_BROWSER_DOM_STORAGE_DOM_STORAGE_TASK_RUNNER_H_
 #define CONTENT_BROWSER_DOM_STORAGE_DOM_STORAGE_TASK_RUNNER_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/sequenced_task_runner.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 42 matching lines @@
 
   // Returns true if the current thread is running on the given |sequence_id|.
   virtual bool IsRunningOnSequence(SequenceID sequence_id) const = 0;
   bool IsRunningOnPrimarySequence() const {
     return IsRunningOnSequence(PRIMARY_SEQUENCE);
   }
   bool IsRunningOnCommitSequence() const {
     return IsRunningOnSequence(COMMIT_SEQUENCE);
   }
 
+  virtual scoped_refptr<base::SequencedTaskRunner> GetSequencedTaskRunner(
+      SequenceID sequence_id) = 0;
+
  protected:
   ~DOMStorageTaskRunner() override {}
 };
 
 // A derived class used in chromium that utilizes a SequenceWorkerPool
 // under dom_storage specific SequenceTokens. The |delayed_task_loop|
 // is used to delay scheduling on the worker pool.
 class CONTENT_EXPORT DOMStorageWorkerPoolTaskRunner :
       public DOMStorageTaskRunner {
  public:
   DOMStorageWorkerPoolTaskRunner(
       base::SequencedWorkerPool* sequenced_worker_pool,
       base::SequencedWorkerPool::SequenceToken primary_sequence_token,
       base::SequencedWorkerPool::SequenceToken commit_sequence_token,
       base::SingleThreadTaskRunner* delayed_task_task_runner);
 
   bool PostDelayedTask(const tracked_objects::Location& from_here,
                        const base::Closure& task,
                        base::TimeDelta delay) override;
 
   bool PostShutdownBlockingTask(const tracked_objects::Location& from_here,
                                 SequenceID sequence_id,
                                 const base::Closure& task) override;
 
   bool IsRunningOnSequence(SequenceID sequence_id) const override;
 
+  scoped_refptr<base::SequencedTaskRunner> GetSequencedTaskRunner(
+      SequenceID sequence_id) override;
+
  protected:
   ~DOMStorageWorkerPoolTaskRunner() override;
 
  private:
 
   base::SequencedWorkerPool::SequenceToken IDtoToken(SequenceID id) const;
 
   const scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   const scoped_refptr<base::SequencedWorkerPool> sequenced_worker_pool_;
   base::SequencedWorkerPool::SequenceToken primary_sequence_token_;
@@ skipping 13 matching lines @@
   bool PostDelayedTask(const tracked_objects::Location& from_here,
                        const base::Closure& task,
                        base::TimeDelta delay) override;
 
   bool PostShutdownBlockingTask(const tracked_objects::Location& from_here,
                                 SequenceID sequence_id,
                                 const base::Closure& task) override;
 
   bool IsRunningOnSequence(SequenceID sequence_id) const override;
 
+  scoped_refptr<base::SequencedTaskRunner> GetSequencedTaskRunner(
+      SequenceID sequence_id) override;
+
  protected:
   ~MockDOMStorageTaskRunner() override;
 
  private:
   const scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_DOM_STORAGE_DOM_STORAGE_TASK_RUNNER_H_