Do not do unnecessary recursive deletes for files.

storage/browser/fileapi/obfuscated_file_util.cc

 // Copyright (c) 2012 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 "storage/browser/fileapi/obfuscated_file_util.h"
 
 #include <queue>
 
 #include "base/files/file_util.h"
 #include "base/format_macros.h"
@@ skipping 1034 matching lines @@
     FileInfo* dest_file_info, int file_flags) {
   SandboxDirectoryDatabase* db = GetDirectoryDatabase(dest_url, true);
 
   base::FilePath root, dest_local_path;
   base::File::Error error = GenerateNewLocalPath(db, context, dest_url, &root,
                                                  &dest_local_path);
   if (error != base::File::FILE_OK)
     return base::File(error);
 
   if (base::PathExists(dest_local_path)) {
-    if (!base::DeleteFile(dest_local_path, true /* recursive */))
+    if (!base::DeleteFile(dest_local_path, false /* recursive */))
       return base::File(base::File::FILE_ERROR_FAILED);
     LOG(WARNING) << "A stray file detected";
     InvalidateUsageCache(context, dest_url.origin(), dest_url.type());
   }
 
   base::File file = NativeFileUtil::CreateOrOpen(dest_local_path, file_flags);
   if (!file.IsValid())
     return file.Pass();
 
   if (!file.created()) {
@@ skipping 21 matching lines @@
 
   base::FilePath root, dest_local_path;
   base::File::Error error = GenerateNewLocalPath(db, context, dest_url, &root,
                                                  &dest_local_path);
   if (error != base::File::FILE_OK)
     return error;
 
   bool created = false;
   if (src_file_path.empty()) {
     if (base::PathExists(dest_local_path)) {
-      if (!base::DeleteFile(dest_local_path, true /* recursive */))
+      if (!base::DeleteFile(dest_local_path, false /* recursive */))
         return base::File::FILE_ERROR_FAILED;
       LOG(WARNING) << "A stray file detected";
       InvalidateUsageCache(context, dest_url.origin(), dest_url.type());
     }
 
     error = NativeFileUtil::EnsureFileExists(dest_local_path, &created);
   } else {
     error = NativeFileUtil::CopyOrMoveFile(
         src_file_path,
         dest_local_path,
@@ skipping 307 matching lines @@
   }
   return file.Pass();
 }
 
 bool ObfuscatedFileUtil::HasIsolatedStorage(const GURL& origin) {
   return special_storage_policy_.get() &&
       special_storage_policy_->HasIsolatedStorage(origin);
 }
 
 }  // namespace storage