Try to speed up SimpleCache index re-sync on Windows.

net/disk_cache/simple/simple_index_file.cc

 // Copyright (c) 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 "net/disk_cache/simple/simple_index_file.h"
 
 #include <utility>
 #include <vector>
 
 #include "base/files/file.h"
@@ skipping 102 matching lines @@
       file.Write(0, static_cast<const char*>(pickle->data()), pickle->size());
   if (bytes_written != base::checked_cast<int>(pickle->size())) {
     simple_util::SimpleCacheDeleteFile(file_name);
     return false;
   }
   return true;
 }
 
 // Called for each cache directory traversal iteration.
 void ProcessEntryFile(SimpleIndex::EntrySet* entries,
-                      const base::FilePath& file_path) {
+                      const base::FilePath& file_path,
+                      base::Time last_accessed,

[jkarlin, 2017/03/27 14:09:15]

Could we instead take a 'const base::FileInfo& file_info' here?

[Maks Orlovich, 2017/03/27 15:25:44]

We don't have a base::FileInfo on the Windows path --- we have a
base::FileEnumerator::FileInfo, which is a different type.

(Not using FileEnumerator on POSIX appears to be done on purpose:

https://chromium.googlesource.com/chromium/src/+/139e21b4cc0ca376b3fdcd13821e...
)

+                      base::Time last_modified,
+                      int64_t size) {
   static const size_t kEntryFilesLength =
       kEntryFilesHashLength + kEntryFilesSuffixLength;
   // Converting to std::string is OK since we never use UTF8 wide chars in our
   // file names.
   const base::FilePath::StringType base_name = file_path.BaseName().value();
   const std::string file_name(base_name.begin(), base_name.end());
   if (file_name.size() != kEntryFilesLength)
     return;
   const base::StringPiece hash_string(
       file_name.begin(), file_name.begin() + kEntryFilesHashLength);
   uint64_t hash_key = 0;
   if (!simple_util::GetEntryHashKeyFromHexString(hash_string, &hash_key)) {
     LOG(WARNING) << "Invalid entry hash key filename while restoring index from"
                  << " disk: " << file_name;
     return;
   }
 
-  File::Info file_info;
-  if (!base::GetFileInfo(file_path, &file_info)) {
-    LOG(ERROR) << "Could not get file info for " << file_path.value();
-    return;
-  }
   base::Time last_used_time;
 #if defined(OS_POSIX)
   // For POSIX systems, a last access time is available. However, it's not
   // guaranteed to be more accurate than mtime. It is no worse though.
-  last_used_time = file_info.last_accessed;
+  last_used_time = last_accessed;
 #endif
   if (last_used_time.is_null())
-    last_used_time = file_info.last_modified;
+    last_used_time = last_modified;
 
   SimpleIndex::EntrySet::iterator it = entries->find(hash_key);
-  base::CheckedNumeric<uint32_t> total_entry_size = file_info.size;
+  base::CheckedNumeric<uint32_t> total_entry_size = size;
 
   if (it == entries->end()) {
     SimpleIndex::InsertInEntrySet(
         hash_key, EntryMetadata(last_used_time, total_entry_size.ValueOrDie()),
         entries);
   } else {
     // Summing up the total size of the entry through all the *_[0-1] files
     total_entry_size += it->second.GetEntrySize();
     it->second.SetEntrySize(total_entry_size.ValueOrDie());
   }
@@ skipping 387 matching lines @@
 bool SimpleIndexFile::LegacyIsIndexFileStale(
     base::Time cache_last_modified,
     const base::FilePath& index_file_path) {
   base::Time index_mtime;
   if (!simple_util::GetMTime(index_file_path, &index_mtime))
     return true;
   return index_mtime < cache_last_modified;
 }
 
 }  // namespace disk_cache