Fix places where "request" is misspelled "requst". Surprisingly, there are several.

content/browser/histogram_synchronizer.h

 // 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.
 
 #ifndef CONTENT_BROWSER_HISTOGRAM_SYNCHRONIZER_H_
 #define CONTENT_BROWSER_HISTOGRAM_SYNCHRONIZER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 100 matching lines @@
   // called, and never merely discarded).
   void SetCallbackTaskAndThread(MessageLoop* callback_thread,
                                 const base::Closure& callback);
 
   void ForceHistogramSynchronizationDoneCallback(int sequence_number);
 
   // Internal helper function, to post task, and record callback stats.
   void InternalPostTask(MessageLoop* thread, const base::Closure& callback);
 
   // Gets a new sequence number to be sent to processes from browser process.
-  int GetNextAvailableSequenceNumber(ProcessHistogramRequester requster);
+  int GetNextAvailableSequenceNumber(ProcessHistogramRequester requester);
 
   // This lock_ protects access to all members.
   base::Lock lock_;
 
   // When a request is made to asynchronously update the histograms, we store
   // the task and thread we use to post a completion notification in
   // callback_ and callback_thread_.
   base::Closure callback_;
   MessageLoop* callback_thread_;
 
@@ skipping 10 matching lines @@
   // The sequence number used by the most recent asynchronous update request to
   // contact all processes.
   int async_sequence_number_;
 
   DISALLOW_COPY_AND_ASSIGN(HistogramSynchronizer);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_HISTOGRAM_SYNCHRONIZER_H_