Support resaving offline page right after it is being deleted

chrome/browser/android/offline_pages/offline_page_mhtml_archiver.cc

Index: chrome/browser/android/offline_pages/offline_page_mhtml_archiver.cc
diff --git a/chrome/browser/android/offline_pages/offline_page_mhtml_archiver.cc b/chrome/browser/android/offline_pages/offline_page_mhtml_archiver.cc
index 73b820c7b4d1748e362133175efd9b18d4350fa5..2087eb84f3b8d274e07edaab8641200932c1da2a 100644
--- a/chrome/browser/android/offline_pages/offline_page_mhtml_archiver.cc
+++ b/chrome/browser/android/offline_pages/offline_page_mhtml_archiver.cc
@@ -4,12 +4,11 @@
 
 #include "chrome/browser/android/offline_pages/offline_page_mhtml_archiver.h"
 
-#include "base/base64.h"
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
-#include "base/sha1.h"
 #include "base/strings/string16.h"
+#include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/public/browser/web_contents.h"
@@ -35,13 +34,13 @@ std::string OfflinePageMHTMLArchiver::GetFileNameExtension() {
 // static
 base::FilePath OfflinePageMHTMLArchiver::GenerateFileName(
     const GURL& url,
-    const std::string& title) {
+    const std::string& title,
+    int64_t archive_id) {
   std::string title_part(title.substr(0, kTitleLengthMax));
-  std::string url_hash(base::SHA1HashString(url.spec()));
-  base::Base64Encode(url_hash, &url_hash);
-  std::string suggested_name(url.host() + kFileNameComponentsSeparator +
-                             title_part + kFileNameComponentsSeparator +
-                             url_hash);
+  std::string suggested_name(
+      url.host() + kFileNameComponentsSeparator +
+      title_part + kFileNameComponentsSeparator +
+      base::Int64ToString(archive_id));
 
   // Substitute spaces out from title.
   base::ReplaceChars(suggested_name, kReplaceChars, kReplaceWith,
@@ -73,16 +72,17 @@ OfflinePageMHTMLArchiver::~OfflinePageMHTMLArchiver() {
 
 void OfflinePageMHTMLArchiver::CreateArchive(
     const base::FilePath& archives_dir,
+    int64_t archive_id,
     const CreateArchiveCallback& callback) {
   DCHECK(callback_.is_null());
   DCHECK(!callback.is_null());
   callback_ = callback;
 
-  GenerateMHTML(archives_dir);
+  GenerateMHTML(archives_dir, archive_id);
 }
 
 void OfflinePageMHTMLArchiver::GenerateMHTML(
-    const base::FilePath& archives_dir) {
+    const base::FilePath& archives_dir, int64_t archive_id) {
   if (archives_dir.empty()) {
     DVLOG(1) << "Archive path was empty. Can't create archive.";
     ReportFailure(ArchiverResult::ERROR_ARCHIVE_CREATION_FAILED);
@@ -107,7 +107,8 @@ void OfflinePageMHTMLArchiver::GenerateMHTML(
   GURL url(web_contents_->GetLastCommittedURL());
   base::string16 title(web_contents_->GetTitle());
   base::FilePath file_path(
-      archives_dir.Append(GenerateFileName(url, base::UTF16ToUTF8(title))));
+      archives_dir.Append(
+          GenerateFileName(url, base::UTF16ToUTF8(title), archive_id)));
 
   web_contents_->GenerateMHTML(
       file_path, base::Bind(&OfflinePageMHTMLArchiver::OnGenerateMHTMLDone,