Fix base64-encoded file uploads not being possible (#12748)

Fix #3804, Fix #5776

spec/controllers/concerns/obfuscate_filename_spec.rb

@@ -1,30 +0,0 @@
-# frozen_string_literal: true
-
-require 'rails_helper'
-
-describe ApplicationController, type: :controller do
-  controller do
-    include ObfuscateFilename
-
-    obfuscate_filename :file
-
-    def file
-      render plain: params[:file]&.original_filename
-    end
-  end
-
-  before do
-    routes.draw { get 'file' => 'anonymous#file' }
-  end
-
-  it 'obfusticates filename if the given parameter is specified' do
-    file = fixture_file_upload('files/imports.txt', 'text/plain')
-    post 'file', params: { file: file }
-    expect(response.body).to end_with '.txt'
-    expect(response.body).not_to include 'imports'
-  end
-
-  it 'does nothing if the given parameter is not specified' do
-    post 'file'
-  end
-end