Files.app: Provide detailed change information on onDirectoryChanged event

chrome/browser/chromeos/drive/file_system_observer.h

Index: chrome/browser/chromeos/drive/file_system_observer.h
diff --git a/chrome/browser/chromeos/drive/file_system_observer.h b/chrome/browser/chromeos/drive/file_system_observer.h
index 1a29e6a88cf11c75d21c3005a3ab31044f82cb4b..20560c4664a6fe37af20f56c6291233ed0ce44d6 100644
--- a/chrome/browser/chromeos/drive/file_system_observer.h
+++ b/chrome/browser/chromeos/drive/file_system_observer.h
@@ -14,6 +14,8 @@ class FilePath;
 
 namespace drive {
 
+class FileChange;
+
 // Interface for classes that need to observe events from classes implementing
 // FileSystemInterface.
 // All events are notified on UI thread.
@@ -22,7 +24,8 @@ class FileSystemObserver {
   // Triggered when a content of a directory has been changed.
   // |directory_path| is a virtual directory path (/drive/...) representing
   // changed directory.
-  virtual void OnDirectoryChanged(const base::FilePath& directory_path) {}
+  virtual void OnDirectoryChanged(const base::FilePath& directory_path,
+                                  const FileChange* file_change) {}
 
   // Triggared when a specific drive error occurred.
   // |type| is a type of the error. |file_name| is a virtual path of the entry.