Files.app: handle UNSUPPORTED_FILESYSTEM errors.

ui/file_manager/file_manager/background/js/volume_manager.js

Index: ui/file_manager/file_manager/background/js/volume_manager.js
diff --git a/ui/file_manager/file_manager/background/js/volume_manager.js b/ui/file_manager/file_manager/background/js/volume_manager.js
index bdcbee12ea44878832227b7908895697ae672846..1abcec03435b16cbda6efab9ff407e8424a2bc04 100644
--- a/ui/file_manager/file_manager/background/js/volume_manager.js
+++ b/ui/file_manager/file_manager/background/js/volume_manager.js
@@ -579,8 +579,11 @@ VolumeManager.prototype.onMountCompleted_ = function(event) {
             'mount',
             event.volumeMetadata.sourcePath);
 
-        var error = event.status === 'success' ? '' : event.status;
-        if (!error || event.status === 'error_unknown_filesystem') {
+        if (event.status === 'success' ||
+            event.status ===
+                VolumeManagerCommon.VolumeError.UNKNOWN_FILESYSTEM ||
+            event.status ===
+                VolumeManagerCommon.VolumeError.UNSUPPORTED_FILESYSTEM) {
           volumeManagerUtil.createVolumeInfo(
               event.volumeMetadata,
               function(volumeInfo) {