[fsp] Add requestUnmount() method together with the request manager.

chrome/browser/chromeos/file_manager/volume_manager.h

Index: chrome/browser/chromeos/file_manager/volume_manager.h
diff --git a/chrome/browser/chromeos/file_manager/volume_manager.h b/chrome/browser/chromeos/file_manager/volume_manager.h
index 3471652ef45bea106ed28e103fa6eeb686f52ebf..160964c8f8c71279456a586c1e5d6a2a4fa3dfb1 100644
--- a/chrome/browser/chromeos/file_manager/volume_manager.h
+++ b/chrome/browser/chromeos/file_manager/volume_manager.h
@@ -5,10 +5,12 @@
 #ifndef CHROME_BROWSER_CHROMEOS_FILE_MANAGER_VOLUME_MANAGER_H_
 #define CHROME_BROWSER_CHROMEOS_FILE_MANAGER_VOLUME_MANAGER_H_
 
+#include <map>
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
+#include "base/files/file.h"
 #include "base/files/file_path.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
@@ -56,6 +58,9 @@ struct VolumeInfo {
   VolumeInfo();
   ~VolumeInfo();
 
+  // The ID for provided file system. If other type, then equal to zero.
+  int file_system_id;
+
   // The ID of the volume.
   std::string volume_id;
 
@@ -169,12 +174,12 @@ class VolumeManager : public KeyedService,
       const std::string& device_path) OVERRIDE;
 
   // chromeos::file_system_provider::Observer overrides.
-  virtual void OnProvidedFileSystemRegistered(
-      const chromeos::file_system_provider::ProvidedFileSystem& file_system)
-      OVERRIDE;
-  virtual void OnProvidedFileSystemUnregistered(
-      const chromeos::file_system_provider::ProvidedFileSystem& file_system)
-      OVERRIDE;
+  virtual void OnProvidedFileSystemMount(
+      const chromeos::file_system_provider::ProvidedFileSystem& file_system,
+      base::File::Error error) OVERRIDE;
+  virtual void OnProvidedFileSystemUnmount(
+      const chromeos::file_system_provider::ProvidedFileSystem& file_system,
+      base::File::Error error) OVERRIDE;
 
   // Called on change to kExternalStorageDisabled pref.
   void OnExternalStorageDisabledChanged();