Make URLFetcherFileWriter::Finish() skip closing file when there is an error

components/precache/core/precache_fetcher.cc

 // 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.
 
 #include "components/precache/core/precache_fetcher.h"
 
 #include <algorithm>
 #include <limits>
 #include <utility>
 #include <vector>
@@ skipping 134 matching lines @@
   int Initialize(const net::CompletionCallback& callback) override {
     return net::OK;
   }
 
   int Write(net::IOBuffer* buffer,
             int num_bytes,
             const net::CompletionCallback& callback) override {
     return num_bytes;
   }
 
-  int Finish(const net::CompletionCallback& callback) override {
+  int Finish(int net_error, const net::CompletionCallback& callback) override {
     return net::OK;
   }
 };
 
 // Returns the base64 encoded resource URL hashes. The resource URLs are hashed
 // individually, and 8 bytes of each hash is appended together, which is then
 // encoded to base64.
 std::string GetResourceURLBase64Hash(const std::vector<GURL>& urls) {
   // Each resource hash uses 8 bytes, instead of the 20 bytes of sha1 hash, as a
   // tradeoff between sending more bytes and reducing hash collisions.
@@ skipping 598 matching lines @@
       remaining = 0;
     quota_.set_remaining(
         used_bytes > quota_.remaining() ? 0U : quota_.remaining() - used_bytes);
     db_task_runner_->PostTask(
         FROM_HERE,
         base::Bind(&PrecacheDatabase::SaveQuota, precache_database_, quota_));
   }
 }
 
 }  // namespace precache