Support cancellation of non-yet-running jobs in drive::JobScheduler.

chrome/browser/chromeos/drive/job_queue.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_CHROMEOS_DRIVE_JOB_QUEUE_H_
 #define CHROME_BROWSER_CHROMEOS_DRIVE_JOB_QUEUE_H_
 
 #include <deque>
 #include <set>
 #include <vector>
@@ skipping 28 matching lines @@
   // Marks a running job |id| as finished running. This decreases the count
   // of running parallel jobs and makes room for other jobs to be popped.
   void MarkFinished(JobID id);
 
   // Generates a string representing the internal state for logging.
   std::string ToString() const;
 
   // Gets the total number of jobs in the queue.
   size_t GetNumberOfJobs() const;
 
+  // Removes the job from the queue.
+  void Remove(JobID id);
+
  private:
   size_t num_max_concurrent_jobs_;
   std::vector<std::deque<JobID> > queue_;
   std::set<JobID> running_;
 
   DISALLOW_COPY_AND_ASSIGN(JobQueue);
 };
 
 }  // namespace drive
 
 #endif  // CHROME_BROWSER_CHROMEOS_DRIVE_JOB_QUEUE_H_