Remove simple_util::GetMTime from simple cache.

net/disk_cache/simple/simple_backend_impl.cc

Index: net/disk_cache/simple/simple_backend_impl.cc
diff --git a/net/disk_cache/simple/simple_backend_impl.cc b/net/disk_cache/simple/simple_backend_impl.cc
index 4aed36c78fc6c7db72720e3dcd84a380e72dca77..c8ff759b80c34e2348c26d2e11541ab7c0b91d7d 100644
--- a/net/disk_cache/simple/simple_backend_impl.cc
+++ b/net/disk_cache/simple/simple_backend_impl.cc
@@ -403,9 +403,10 @@ SimpleBackendImpl::DiskStatResult SimpleBackendImpl::InitCacheStructureOnDisk(
                << path.LossyDisplayName();
     result.net_error = net::ERR_FAILED;
   } else {
-    bool mtime_result =
-        disk_cache::simple_util::GetMTime(path, &result.cache_dir_mtime);
-    DCHECK(mtime_result);
+    base::PlatformFileInfo file_info;
+    bool file_info_result = file_util::GetFileInfo(path, &file_info);
+    DCHECK(file_info_result);
+    result.cache_dir_mtime = file_info.last_modified;
     if (!result.max_size) {
       int64 available = base::SysInfo::AmountOfFreeDiskSpace(path);
       if (available < 0)