[fsp] Pass more detailed errors to the providing extension.

chrome/browser/chromeos/file_system_provider/fake_provided_file_system.cc

Index: chrome/browser/chromeos/file_system_provider/fake_provided_file_system.cc
diff --git a/chrome/browser/chromeos/file_system_provider/fake_provided_file_system.cc b/chrome/browser/chromeos/file_system_provider/fake_provided_file_system.cc
index 3f415e269791e86bf5fb07ecba1c48fcda07c495..cc676f810231c148b820c2eeaab30c12b99d840d 100644
--- a/chrome/browser/chromeos/file_system_provider/fake_provided_file_system.cc
+++ b/chrome/browser/chromeos/file_system_provider/fake_provided_file_system.cc
@@ -367,14 +367,15 @@ void FakeProvidedFileSystem::RemoveObserver(
   observers_.RemoveObserver(observer);
 }
 
-bool FakeProvidedFileSystem::Notify(
+void FakeProvidedFileSystem::Notify(
     const base::FilePath& entry_path,
     bool recursive,
     storage::WatcherManager::ChangeType change_type,
     scoped_ptr<ProvidedFileSystemObserver::Changes> changes,
-    const std::string& tag) {
+    const std::string& tag,
+    const storage::AsyncFileUtil::StatusCallback& callback) {
   NOTREACHED();
-  return false;
+  callback.Run(base::File::FILE_ERROR_SECURITY);
 }
 
 ProvidedFileSystemInterface* FakeProvidedFileSystem::Create(