Fix empty details view after renaming a file

"FileList._updateDetailsView" expects either a file name (as a string)
or a file model (as an "OCA.File.FileInfoModel"), but when called
through "updateInList" an "OC.Files.FileInfo" object was given instead.
As the given attribute was not a model "_updateDetailsView" treated it
as a file name and tried to get the model for that file, which failed
and caused the details view to be emptied.

Signed-off-by: Daniel Calviño Sánchez <danxuliu@gmail.com>