[fsp] Allow to create multiple observers for a directory, up to one per origin.

chrome/browser/chromeos/file_system_provider/provided_file_system_interface.h

 // 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_PROVIDED_FILE_SYSTEM_INTERFACE_H_
 #define CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_PROVIDED_FILE_SYSTEM_INTERFACE_H_
 
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/files/file.h"
 #include "base/files/file_path.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
 #include "chrome/browser/chromeos/file_system_provider/observed_entry.h"
 #include "chrome/browser/chromeos/file_system_provider/provided_file_system_observer.h"
 #include "storage/browser/fileapi/async_file_util.h"
+#include "url/gurl.h"
 
 class EventRouter;
 
 namespace base {
 class Time;
 }  // namespace base
 
 namespace net {
 class IOBuffer;
 }  // namespace net
@@ skipping 140 matching lines @@
   // Requests writing to a file previously opened with |file_handle|.
   virtual AbortCallback WriteFile(
       int file_handle,
       net::IOBuffer* buffer,
       int64 offset,
       int length,
       const storage::AsyncFileUtil::StatusCallback& callback) = 0;
 
   // Requests observing a directory.
   virtual AbortCallback ObserveDirectory(
+      const GURL& origin,
       const base::FilePath& directory_path,
       bool recursive,
+      bool persistent,
       const storage::AsyncFileUtil::StatusCallback& callback) = 0;
 
   // Requests unobserving an entry, which is immediately removed from the
   // internal list, hence the operation is not abortable.
   virtual void UnobserveEntry(
+      const GURL& origin,
       const base::FilePath& entry_path,
       bool recursive,
       const storage::AsyncFileUtil::StatusCallback& callback) = 0;
 
   // Notifies about changes to the observed entries within the file system.
   // Invoked by the file system implementation. Returns false if the
   // notification arguments are malformed or the entry is not observed anymore.
   virtual bool Notify(const base::FilePath& observed_path,
                       bool recursive,
                       ProvidedFileSystemObserver::ChangeType change_type,
@@ skipping 16 matching lines @@
   virtual void RemoveObserver(ProvidedFileSystemObserver* observer) = 0;
 
   // Returns a weak pointer to this object.
   virtual base::WeakPtr<ProvidedFileSystemInterface> GetWeakPtr() = 0;
 };
 
 }  // namespace file_system_provider
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_FILE_SYSTEM_PROVIDER_PROVIDED_FILE_SYSTEM_INTERFACE_H_