Make SDCH classes IO-thread-only. Remove TSan suppression.

chrome/browser/net/sdch_dictionary_fetcher.h

 // Copyright (c) 2011 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.
 
 // Support modularity by calling to load a new SDCH filter dictionary.
 // Note that this sort of calling can't be done in the /net directory, as it has
 // no concept of the HTTP cache (which is only visible at the browser level).
 
 #ifndef CHROME_BROWSER_NET_SDCH_DICTIONARY_FETCHER_H_
 #define CHROME_BROWSER_NET_SDCH_DICTIONARY_FETCHER_H_
 #pragma once
 
 #include <queue>
 #include <set>
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/task.h"
+#include "base/threading/non_thread_safe.h"
 #include "content/public/common/url_fetcher_delegate.h"
 #include "net/base/sdch_manager.h"
 
-class SdchDictionaryFetcher : public content::URLFetcherDelegate,
-                              public net::SdchFetcher {
+class SdchDictionaryFetcher
+    : public content::URLFetcherDelegate,
+      public net::SdchFetcher,
+      public base::NonThreadSafe {
  public:
   SdchDictionaryFetcher();
   virtual ~SdchDictionaryFetcher();
 
   // Stop fetching dictionaries, and abandon any current URLFetcheer operations
   // so that the IO thread can be stopped.
   static void Shutdown();
 
   // Implementation of SdchFetcher class.
   // This method gets the requested dictionary, and then calls back into the
@@ skipping 42 matching lines @@
   // bandwidth trying repeatedly).
   // The following set lists all the dictionary URLs that we've tried to load,
   // so that we won't try to load from an URL more than once.
   // TODO(jar): Try to augment the SDCH proposal to include this restiction.
   std::set<GURL> attempted_load_;
 
   DISALLOW_COPY_AND_ASSIGN(SdchDictionaryFetcher);
 };
 
 #endif  // CHROME_BROWSER_NET_SDCH_DICTIONARY_FETCHER_H_