Prevent error in file path

ios/chrome/browser/reading_list/url_downloader.cc

 // Copyright 2016 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 "ios/chrome/browser/reading_list/url_downloader.h"
 
 #include <string>
 #include <vector>
 
 #include "base/files/file_path.h"
@@ skipping 148 matching lines @@
       web::WebThread::GetTaskRunnerForThread(web::WebThread::FILE).get(),
       FROM_HERE,
       base::Bind(&URLDownloader::SaveDistilledHTML, base::Unretained(this),
                  page_url, images_block, block_html),
       base::Bind(&URLDownloader::DownloadCompletionHandler,
                  base::Unretained(this), page_url, title));
 }
 
 URLDownloader::SuccessState URLDownloader::SaveDistilledHTML(
     const GURL& url,
-    std::vector<dom_distiller::DistillerViewerInterface::ImageInfo> images,
-    std::string html) {
+    const std::vector<dom_distiller::DistillerViewerInterface::ImageInfo>&
+        images,
+    const std::string& html) {
   if (CreateOfflineURLDirectory(url)) {
     return SaveHTMLForURL(SaveAndReplaceImagesInHTML(url, html, images), url)
                ? DOWNLOAD_SUCCESS
                : ERROR_PERMANENT;
   }
   return ERROR_PERMANENT;
 }
 
 base::FilePath URLDownloader::OfflineDirectoryPath() {
-  return base_directory_.Append(kOfflineDirectory);
+  return base_directory_.Append(FILE_PATH_LITERAL(kOfflineDirectory));
 }
 
 base::FilePath URLDownloader::OfflineURLDirectoryPath(const GURL& url) {
   std::string hash = base::MD5String(url.spec());
-  return OfflineDirectoryPath().Append(hash);
+  return OfflineDirectoryPath().AppendASCII(hash);
 }
 
 base::FilePath URLDownloader::OfflineURLPagePath(const GURL& url) {
-  return OfflineURLDirectoryPath(url).Append("page.html");
+  return OfflineURLDirectoryPath(url).Append(FILE_PATH_LITERAL("page.html"));
 }
 
 bool URLDownloader::CreateOfflineURLDirectory(const GURL& url) {
   base::FilePath path = OfflineURLDirectoryPath(url);
   if (!DirectoryExists(path)) {
     return CreateDirectoryAndGetError(path, nil);
   }
   return true;
 }
 
@@ skipping 31 matching lines @@
   return mutable_html;
 }
 
 bool URLDownloader::SaveHTMLForURL(std::string html, const GURL& url) {
   if (html.empty()) {
     return false;
   }
   base::FilePath path = OfflineURLPagePath(url);
   return base::WriteFile(path, html.c_str(), html.length()) > 0;
 }