diff --git a/Gemfile b/Gemfile
index 6bb6b036719587ccdf4c6c8b92f18acddd6ef560..1c378c7a68932966db8a4b034945124fcb6791e1 100644
--- a/Gemfile
+++ b/Gemfile
@@ -8,7 +8,6 @@ else
   gem 'arel'
 end
 
-gem 'minitest', '~> 3.2.0'
 gem 'mocha', '>= 0.11.2', :require => false
 gem 'rack-test', github: "brynary/rack-test"
 gem 'bcrypt-ruby', '~> 3.0.0'
diff --git a/activesupport/activesupport.gemspec b/activesupport/activesupport.gemspec
index fa38d5c1e3268df5b53c380164a5c517e4ba4efa..836bc2f9cf435a7c5e6a77c633f5013b6028694d 100644
--- a/activesupport/activesupport.gemspec
+++ b/activesupport/activesupport.gemspec
@@ -22,4 +22,5 @@
   s.add_dependency('i18n',       '~> 0.6')
   s.add_dependency('multi_json', '~> 1.3')
   s.add_dependency('tzinfo',     '~> 0.3.33')
+  s.add_dependency('minitest',   '~> 3.2')
 end
diff --git a/activesupport/lib/active_support/test_case.rb b/activesupport/lib/active_support/test_case.rb
index b6abc3b561630a4132b2b66a1c45c0aef3c0d39a..a6f3b437922af3544a2a1d581ee7e2169866398b 100644
--- a/activesupport/lib/active_support/test_case.rb
+++ b/activesupport/lib/active_support/test_case.rb
@@ -1,3 +1,4 @@
+gem 'minitest' # make sure we get the gem, not stdlib
 require 'minitest/spec'
 require 'active_support/testing/setup_and_teardown'
 require 'active_support/testing/assertions'
diff --git a/activesupport/lib/active_support/testing/setup_and_teardown.rb b/activesupport/lib/active_support/testing/setup_and_teardown.rb
index ddb7396aa95dc363912e186eea007b2c0ab79053..a65148cf1f9757b8cbbaaa40fa4d1d97f15c56f0 100644
--- a/activesupport/lib/active_support/testing/setup_and_teardown.rb
+++ b/activesupport/lib/active_support/testing/setup_and_teardown.rb
@@ -4,20 +4,11 @@
 module ActiveSupport
   module Testing
     module SetupAndTeardown
-
-      PASSTHROUGH_EXCEPTIONS = [
-        NoMemoryError,
-        SignalException,
-        Interrupt,
-        SystemExit
-      ]
-
       extend ActiveSupport::Concern
 
       included do
         include ActiveSupport::Callbacks
         define_callbacks :setup, :teardown
-
       end
 
       module ClassMethods
diff --git a/guides/source/4_0_release_notes.textile b/guides/source/4_0_release_notes.textile
index e1d6b42e6cc3bf8c7eb34919aa7be98824ba0c01..270c0e39c54409fdeb612982b40bcf2762269f1b 100644
--- a/guides/source/4_0_release_notes.textile
+++ b/guides/source/4_0_release_notes.textile
@@ -329,6 +329,20 @@ Moved into a separate gem <tt>sprockets-rails</tt>.
 
 h3. Active Record
 
+* Add <tt>add_reference</tt> and <tt>remove_reference</tt> schema statements. Aliases, <tt>add_belongs_to</tt> and <tt>remove_belongs_to</tt> are acceptable. References are reversible.
+
+<ruby>
+# Create a user_id column
+add_reference(:products, :user)
+
+# Create a supplier_id, supplier_type columns and appropriate index
+add_reference(:products, :supplier, polymorphic: true, index: true)
+
+# Remove polymorphic reference
+remove_reference(:products, :supplier, polymorphic: true)
+</ruby>
+
+
 * Add <tt>:default</tt> and <tt>:null</tt> options to <tt>column_exists?</tt>.
 
 <ruby>
@@ -343,7 +357,7 @@ User.where(:age => 30)      # => returns the relation
 User.where(:age => 30).to_a # => executes the query and returns the loaded objects, as before
 </ruby>
 
-* Add <tt>collation</tt> and <tt>ctype</tt> support to PostgreSQL. These are available for PostgreSQL 8.4 or later.
+* Add <tt>:collation</tt> and <tt>:ctype</tt> support to PostgreSQL. These are available for PostgreSQL 8.4 or later.
 
 <yaml>
 development:
@@ -506,7 +520,7 @@ Post.find_by! name: 'Spartacus'
 
 * Added <tt>ActiveRecord::Base#slice</tt> to return a hash of the given methods with their names as keys and returned values as values.
 
-* Remove IdentityMap - IdentityMap has never graduated to be an "enabled-by-default" feature, due to some inconsistencies with associations, as described in this commit: https://github.com/rails/rails/commit/302c912bf6bcd0fa200d964ec2dc4a44abe328a6. Hence the removal from the codebase, until such issues are fixed.
+* Remove IdentityMap - IdentityMap has never graduated to be an "enabled-by-default" feature, due to some inconsistencies with associations, as described in this "commit":https://github.com/rails/rails/commit/302c912bf6bcd0fa200d964ec2dc4a44abe328a6. Hence the removal from the codebase, until such issues are fixed.
 
 * Added a feature to dump/load internal state of +SchemaCache+ instance because we want to boot more quickly when we have many models.
 
@@ -708,7 +722,7 @@ h4(#activemodel_deprecations). Deprecations
 
 h3. Active Resource
 
-* Active Resource is removed from Rails 4.0 and is now a separate gem. TODO: put a link to the gem here.
+* Active Resource is removed from Rails 4.0 and is now a separate "gem":https://github.com/rails/activeresource.
 
 h3. Active Support