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

chrome/browser/chromeos/file_manager/volume_manager.cc

Index: chrome/browser/chromeos/file_manager/volume_manager.cc
diff --git a/chrome/browser/chromeos/file_manager/volume_manager.cc b/chrome/browser/chromeos/file_manager/volume_manager.cc
index a2feaa0a90190d37b9bc31d5b892fa63869325f1..aa0edf41df01a802e894dd8043da2f89cd6a2533 100644
--- a/chrome/browser/chromeos/file_manager/volume_manager.cc
+++ b/chrome/browser/chromeos/file_manager/volume_manager.cc
@@ -211,6 +211,7 @@ VolumeInfo CreateProvidedFileSystemVolumeInfo(
   volume_info.is_parent = true;
   volume_info.is_read_only = true;
   volume_info.volume_id = GenerateVolumeId(volume_info);
+  volume_info.file_system_id = file_system.file_system_id();
   return volume_info;
 }
 
@@ -296,7 +297,7 @@ void VolumeManager::Initialize() {
     file_system_provider_service_->AddObserver(this);
 
     std::vector<ProvidedFileSystem> provided_file_systems =
-        file_system_provider_service_->GetRegisteredFileSystems();
+        file_system_provider_service_->GetMountedFileSystems();
     for (size_t i = 0; i < provided_file_systems.size(); ++i) {
       VolumeInfo volume_info =
           CreateProvidedFileSystemVolumeInfo(provided_file_systems[i]);
@@ -619,16 +620,28 @@ void VolumeManager::OnFormatEvent(
   NOTREACHED();
 }
 
-void VolumeManager::OnProvidedFileSystemRegistered(
-    const chromeos::file_system_provider::ProvidedFileSystem& file_system) {
+void VolumeManager::OnProvidedFileSystemMount(
+    const chromeos::file_system_provider::ProvidedFileSystem& file_system,
+    base::File::Error error) {
   VolumeInfo volume_info = CreateProvidedFileSystemVolumeInfo(file_system);
-  DoMountEvent(chromeos::MOUNT_ERROR_NONE, volume_info, false /* remounting */);
-}
-
-void VolumeManager::OnProvidedFileSystemUnregistered(
-    const chromeos::file_system_provider::ProvidedFileSystem& file_system) {
+  // TODO(mtomasz): Introduce own type, and avoid using MountError internally,
+  // since it is related to cros disks only.
+  const chromeos::MountError mount_error = error == base::File::FILE_OK
+                                               ? chromeos::MOUNT_ERROR_NONE
+                                               : chromeos::MOUNT_ERROR_UNKNOWN;
+  DoMountEvent(mount_error, volume_info, false /* remounting */);
+}
+
+void VolumeManager::OnProvidedFileSystemUnmount(
+    const chromeos::file_system_provider::ProvidedFileSystem& file_system,
+    base::File::Error error) {
+  // TODO(mtomasz): Introduce own type, and avoid using MountError internally,
+  // since it is related to cros disks only.
+  const chromeos::MountError mount_error = error == base::File::FILE_OK
+                                               ? chromeos::MOUNT_ERROR_NONE
+                                               : chromeos::MOUNT_ERROR_UNKNOWN;
   VolumeInfo volume_info = CreateProvidedFileSystemVolumeInfo(file_system);
-  DoUnmountEvent(chromeos::MOUNT_ERROR_NONE, volume_info);
+  DoUnmountEvent(mount_error, volume_info);
 }
 
 void VolumeManager::OnExternalStorageDisabledChanged() {