[fsp] Separate logic for saving/restoring state to a separate class.

chrome/browser/chromeos/file_system_provider/provided_file_system_unittest.cc

 // Copyright 2014 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 "chrome/browser/chromeos/file_system_provider/provided_file_system.h"
 
 #include <string>
 #include <vector>
 
 #include "base/files/file.h"
@@ skipping 106 matching lines @@
     const ProvidedFileSystemObserver::ChildChanges child_changes_;
 
     DISALLOW_COPY_AND_ASSIGN(ChangeEvent);
   };
 
   Observer() : list_changed_counter_(0), tag_updated_counter_(0) {}
 
   // ProvidedFileSystemInterfaceObserver overrides.
   virtual void OnObservedEntryChanged(
       const ProvidedFileSystemInfo& file_system_info,
-      const base::FilePath& observed_path,
+      const ObservedEntry& observed_entry,
       ProvidedFileSystemObserver::ChangeType change_type,
       const ProvidedFileSystemObserver::ChildChanges& child_changes,
       const base::Closure& callback) override {
     EXPECT_EQ(kFileSystemId, file_system_info.file_system_id());
     change_events_.push_back(new ChangeEvent(change_type, child_changes));
     base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE, callback);
   }
 
   virtual void OnObservedEntryTagUpdated(
       const ProvidedFileSystemInfo& file_system_info,
-      const base::FilePath& observed_path,
-      const std::string& tag) override {
+      const ObservedEntry& observed_entry) override {
     EXPECT_EQ(kFileSystemId, file_system_info.file_system_id());
     ++tag_updated_counter_;
   }
 
   virtual void OnObservedEntryListChanged(
       const ProvidedFileSystemInfo& file_system_info,
       const ObservedEntries& observed_entries) override {
     EXPECT_EQ(kFileSystemId, file_system_info.file_system_id());
     ++list_changed_counter_;
   }
@@ skipping 451 matching lines @@
     EXPECT_EQ(0u, observed_entries->size());
     EXPECT_EQ(2, observer.list_changed_counter());
     EXPECT_EQ(2, observer.tag_updated_counter());
   }
 
   provided_file_system_->RemoveObserver(&observer);
 }
 
 }  // namespace file_system_provider
 }  // namespace chromeos