[fsp] Add support for observing entries and notifying about changes.

chrome/browser/chromeos/file_system_provider/fake_provided_file_system.h

Index: chrome/browser/chromeos/file_system_provider/fake_provided_file_system.h
diff --git a/chrome/browser/chromeos/file_system_provider/fake_provided_file_system.h b/chrome/browser/chromeos/file_system_provider/fake_provided_file_system.h
index f9dd955fa9e6b3aafefbd450a6ca0136ea218395..2056aed61d46d776aa2b32a0ffaa963b2731c462 100644
--- a/chrome/browser/chromeos/file_system_provider/fake_provided_file_system.h
+++ b/chrome/browser/chromeos/file_system_provider/fake_provided_file_system.h
@@ -12,6 +12,7 @@
 #include "base/callback.h"
 #include "base/memory/linked_ptr.h"
 #include "base/memory/weak_ptr.h"
+#include "base/observer_list.h"
 #include "base/task/cancelable_task_tracker.h"
 #include "chrome/browser/chromeos/file_system_provider/provided_file_system_info.h"
 #include "chrome/browser/chromeos/file_system_provider/provided_file_system_interface.h"
@@ -124,6 +125,10 @@ class FakeProvidedFileSystem : public ProvidedFileSystemInterface {
       const storage::AsyncFileUtil::StatusCallback& callback) OVERRIDE;
   virtual const ProvidedFileSystemInfo& GetFileSystemInfo() const OVERRIDE;
   virtual RequestManager* GetRequestManager() OVERRIDE;
+  virtual ObservedEntries* GetObservedEntries() OVERRIDE;
+  virtual void AddObserver(Observer* observer) OVERRIDE;
+  virtual void RemoveObserver(Observer* observer) OVERRIDE;
+  virtual ObserverList<Observer>* GetObservers() OVERRIDE;
   virtual base::WeakPtr<ProvidedFileSystemInterface> GetWeakPtr() OVERRIDE;
 
   // Factory callback, to be used in Service::SetFileSystemFactory(). The
@@ -156,6 +161,7 @@ class FakeProvidedFileSystem : public ProvidedFileSystemInterface {
   OpenedFilesMap opened_files_;
   int last_file_handle_;
   base::CancelableTaskTracker tracker_;
+  ObserverList<Observer> observers_;
 
   base::WeakPtrFactory<FakeProvidedFileSystem> weak_ptr_factory_;
   DISALLOW_COPY_AND_ASSIGN(FakeProvidedFileSystem);