[translate] Add translate ranker model loader.

components/translate/core/browser/translate_url_fetcher.cc

 // 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.
 
 #include "components/translate/core/browser/translate_url_fetcher.h"
 
 #include "components/data_use_measurement/core/data_use_user_data.h"
 #include "components/translate/core/browser/translate_download_manager.h"
 #include "net/base/load_flags.h"
 #include "net/http/http_status_code.h"
@@ skipping 13 matching lines @@
                                                    state_(IDLE),
                                                    retry_count_(0) {
 }
 
 TranslateURLFetcher::~TranslateURLFetcher() {
 }
 
 bool TranslateURLFetcher::Request(
     const GURL& url,
     const TranslateURLFetcher::Callback& callback) {
-  // This function is not supposed to be called before previous operaion is not
+  // This function is not supposed to be called if the previous operation is not
   // finished.
   if (state_ == REQUESTING) {
     NOTREACHED();
     return false;
   }
 
   if (retry_count_ >= kMaxRetry)
     return false;
   retry_count_++;
 
@@ skipping 31 matching lines @@
   } else {
     state_ = FAILED;
   }
 
   // Transfer URLFetcher's ownership before invoking a callback.
   std::unique_ptr<const net::URLFetcher> delete_ptr(fetcher_.release());
   callback_.Run(id_, state_ == COMPLETED, data);
 }
 
 }  // namespace translate