No more need rubygems here.

activemodel/test/cases/helper.rb

@@ -10,5 +10,4 @@
 # Show backtraces for deprecated behavior for quicker cleanup.
 ActiveSupport::Deprecation.debug = true
 
-require 'rubygems'
 require 'test/unit'

activeresource/test/abstract_unit.rb

@@ -3,7 +3,6 @@
 lib = File.expand_path("#{File.dirname(__FILE__)}/../lib")
 $:.unshift(lib) unless $:.include?('lib') || $:.include?(lib)
 
-require 'rubygems'
 require 'test/unit'
 require 'active_resource'
 require 'active_support'

railties/test/isolation/abstract_unit.rb

@@ -8,8 +8,6 @@
 # Rails booted up.
 require 'fileutils'
 
-# TODO: Remove rubygems when possible
-require 'rubygems'
 require 'test/unit'
 
 # TODO: Remove setting this magic constant