drive: FileCache::Store marks the entry as dirty if empty MD5 is given

chrome/browser/chromeos/drive/file_system/download_operation.cc

Index: chrome/browser/chromeos/drive/file_system/download_operation.cc
diff --git a/chrome/browser/chromeos/drive/file_system/download_operation.cc b/chrome/browser/chromeos/drive/file_system/download_operation.cc
index 6bb88acaf4b3d4a6c7c55c8e60a033ef01e4a448..43c8946938b501472f3d824a9e36bac357ced844 100644
--- a/chrome/browser/chromeos/drive/file_system/download_operation.cc
+++ b/chrome/browser/chromeos/drive/file_system/download_operation.cc
@@ -4,7 +4,6 @@
 
 #include "chrome/browser/chromeos/drive/file_system/download_operation.h"
 
-#include "base/callback_helpers.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
@@ -89,14 +88,10 @@ FileError CheckPreConditionForEnsureFileDownloaded(
     base::FilePath empty_file;
     if (!base::CreateTemporaryFileInDir(temporary_file_directory, &empty_file))
       return FILE_ERROR_FAILED;
-    error = cache->Store(local_id, base::MD5String(""), empty_file,
+    error = cache->Store(local_id, std::string(), empty_file,
                          internal::FileCache::FILE_OPERATION_MOVE);
     if (error != FILE_ERROR_OK)
       return error;
-    scoped_ptr<base::ScopedClosureRunner> file_closer;
-    error = cache->OpenForWrite(entry->local_id(), &file_closer);
-    if (error != FILE_ERROR_OK)
-      return error;
 
     if (!cache->GetCacheEntry(local_id, &cache_entry))
       return FILE_ERROR_NOT_FOUND;