Revert "FBTF: Move the TabRestoreService::Observer into its own file."

chrome/browser/sessions/tab_restore_service_observer.h

Index: chrome/browser/sessions/tab_restore_service_observer.h
diff --git a/chrome/browser/sessions/tab_restore_service_observer.h b/chrome/browser/sessions/tab_restore_service_observer.h
deleted file mode 100644
index e4d21184ffb9d0faf1b6717556afa860f04178ee..0000000000000000000000000000000000000000
--- a/chrome/browser/sessions/tab_restore_service_observer.h
+++ /dev/null
@@ -1,25 +0,0 @@
-// Copyright (c) 2010 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.
-
-#ifndef CHROME_BROWSER_SESSIONS_TAB_RESTORE_SERVICE_OBSERVER_H_
-#define CHROME_BROWSER_SESSIONS_TAB_RESTORE_SERVICE_OBSERVER_H_
-
-class TabRestoreService;
-
-// Observer is notified when the set of entries managed by TabRestoreService
-// changes in some way.
-class TabRestoreServiceObserver {
- public:
-  // Sent when the set of entries changes in some way.
-  virtual void TabRestoreServiceChanged(TabRestoreService* service) = 0;
-
-  // Sent to all remaining Observers when TabRestoreService's
-  // destructor is run.
-  virtual void TabRestoreServiceDestroyed(TabRestoreService* service) = 0;
-
- protected:
-  virtual ~TabRestoreServiceObserver() {}
-};
-
-#endif  // CHROME_BROWSER_SESSIONS_TAB_RESTORE_SERVICE_OBSERVER_H_