Introduce TranslateService and TranslateDownloadManager

components/translate/core/browser/translate_url_fetcher.h

 // Copyright 2014 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 COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_URL_FETCHER_H_
 #define COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_URL_FETCHER_H_
 
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "net/url_request/url_fetcher_delegate.h"
 #include "url/gurl.h"
 
-class TranslateDelegate;
-
+// Downloads raw Translate data such as the Translate script and the language
+// list.
 class TranslateURLFetcher : public net::URLFetcherDelegate {
  public:
   // Callback type for Request().
   typedef base::Callback<void(int, bool, const std::string&)> Callback;
 
   // Represents internal state if the fetch is completed successfully.
   enum State {
     IDLE,        // No fetch request was issued.
     REQUESTING,  // A fetch request was issued, but not finished yet.
     COMPLETED,   // The last fetch request was finished successfully.
     FAILED,      // The last fetch request was finished with a failure.
   };
 
-  // |delegate| is expected to outlive the TranslateURLFetcher.
-  explicit TranslateURLFetcher(int id, TranslateDelegate* delegate);
+  explicit TranslateURLFetcher(int id);
   virtual ~TranslateURLFetcher();
 
   int max_retry_on_5xx() {
     return max_retry_on_5xx_;
   }
   void set_max_retry_on_5xx(int count) {
     max_retry_on_5xx_ = count;
   }
 
   const std::string& extra_request_header() {
@@ skipping 15 matching lines @@
   // net::URLFetcherDelegate implementation:
   virtual void OnURLFetchComplete(const net::URLFetcher* source) OVERRIDE;
 
  private:
   // URL to send the request.
   GURL url_;
 
   // ID which is assigned to the URLFetcher.
   const int id_;
 
-  // Used to get information from the embedder of Translate.
-  TranslateDelegate* translate_delegate_;
-
   // Internal state.
   enum State state_;
 
   // URLFetcher instance.
   scoped_ptr<net::URLFetcher> fetcher_;
 
   // Callback passed at Request(). It will be invoked when an asynchronous
   // fetch operation is finished.
   Callback callback_;
 
   // Counts how many times did it try to fetch the language list.
   int retry_count_;
 
   // Max number how many times to retry on the server error
   int max_retry_on_5xx_;
 
   // An extra HTTP request header
   std::string extra_request_header_;
 
   DISALLOW_COPY_AND_ASSIGN(TranslateURLFetcher);
 };
 
 #endif  // COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_URL_FETCHER_H_