drive: Add "Delta Update Status" section to chrome:drive-internals

chrome/browser/chromeos/drive/drive_file_system_interface.h

Index: chrome/browser/chromeos/drive/drive_file_system_interface.h
diff --git a/chrome/browser/chromeos/drive/drive_file_system_interface.h b/chrome/browser/chromeos/drive/drive_file_system_interface.h
index 4b115ebe304f4d46030aed7d7b85df4ca7120515..296efcf1b65596d7c1da2c72f9fc55f3dadce512 100644
--- a/chrome/browser/chromeos/drive/drive_file_system_interface.h
+++ b/chrome/browser/chromeos/drive/drive_file_system_interface.h
@@ -10,6 +10,7 @@
 
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/chromeos/drive/drive_cache.h"
+#include "chrome/browser/chromeos/drive/drive_file_system_metadata.h"
 #include "chrome/browser/chromeos/drive/drive_resource_metadata.h"
 #include "chrome/browser/google_apis/gdata_operations.h"
 
@@ -38,15 +39,6 @@ struct SearchResultInfo {
   bool is_directory;
 };
 
-// Metadata of DriveFileSystem. Used by DriveFileSystem::GetMetadata().
-struct DriveFileSystemMetadata {
-  DriveFileSystemMetadata() : largest_changestamp(0), origin("?") {}
-  ~DriveFileSystemMetadata() {}
-
-  int64 largest_changestamp;
-  std::string origin;
-};
-
 // Used to get files from the file system.
 typedef base::Callback<void(DriveFileError error,
                             const FilePath& file_path,