Add a method in DiskMountManager to refresh mount entries in addition to devices.

chromeos/disks/mock_disk_mount_manager.h

Index: chromeos/disks/mock_disk_mount_manager.h
diff --git a/chromeos/disks/mock_disk_mount_manager.h b/chromeos/disks/mock_disk_mount_manager.h
index f7baa8eae8037a8762f2ec63739885651332eef4..e00278acc4f0ae7a1ac371a97dc34dd75ce5bb96 100644
--- a/chromeos/disks/mock_disk_mount_manager.h
+++ b/chromeos/disks/mock_disk_mount_manager.h
@@ -32,7 +32,8 @@ class MockDiskMountManager : public DiskMountManager {
                      const DiskMountManager::Disk*(const std::string&));
   MOCK_CONST_METHOD0(mount_points,
                      const DiskMountManager::MountPointMap&(void));
-  MOCK_METHOD0(RequestMountInfoRefresh, void(void));
+  MOCK_METHOD1(EnsureMountInfoRefreshed,
+               void(const EnsureMountInfoRefreshedCallback&));
   MOCK_METHOD4(MountPath, void(const std::string&, const std::string&,
                                const std::string&, MountType));
   MOCK_METHOD3(UnmountPath, void(const std::string&,
@@ -88,6 +89,10 @@ class MockDiskMountManager : public DiskMountManager {
   const DiskMountManager::Disk* FindDiskBySourcePathInternal(
       const std::string& source_path) const;
 
+  // Is used to implement EnsureMountInfoRefreshed.
+  void EnsureMountInfoRefreshedInternal(
+      const EnsureMountInfoRefreshedCallback& callback);
+
   // Notifies observers about device status update.
   void NotifyDeviceChanged(DeviceEvent event,
                            const std::string& path);