Split recursive Copy/Move into async tasks and support cross operation (in local case)

webkit/fileapi/obfuscated_file_util.cc

Index: webkit/fileapi/obfuscated_file_util.cc
diff --git a/webkit/fileapi/obfuscated_file_util.cc b/webkit/fileapi/obfuscated_file_util.cc
index 9bd64bc1cce38997332cb4f80eb78e9c7657f2aa..dd75118a978bf7f9467c6066989e03dc82f50250 100644
--- a/webkit/fileapi/obfuscated_file_util.cc
+++ b/webkit/fileapi/obfuscated_file_util.cc
@@ -877,8 +877,10 @@ base::PlatformFileError ObfuscatedFileUtil::CreateSnapshotFile(
   *policy = kSnapshotFileLocal;
   base::PlatformFileError error = GetFileInfo(
       context, url, file_info, platform_path);
-  if (error == base::PLATFORM_FILE_OK && file_info->is_directory)
+  if (error == base::PLATFORM_FILE_OK && file_info->is_directory) {
+    *file_info = base::PlatformFileInfo();
     return base::PLATFORM_FILE_ERROR_NOT_A_FILE;
+  }
   return error;
 }