Instead of requiring dependency, only exe if defined

lib/secure_headers/railtie.rb

@@ -1,5 +1,3 @@
-require 'active_support/dependencies'
-
 # rails 3.1+
 if defined?(Rails::Railtie)
   module SecureHeaders
@@ -25,10 +23,12 @@ else
     end
   end
 
-  if ActiveSupport::Dependencies.autoload_paths
-    ActiveSupport::Dependencies.autoload_paths << File.expand_path(File.join("..", "..", "..", "app", "controllers"), __FILE__)
-  else
-    ActiveSupport::Dependencies.autoload_paths = [File.expand_path(File.join("..", "..", "..", "app", "controllers"), __FILE__)]
+  if defined?(ActiveSupport::Dependencies)
+    if ActiveSupport::Dependencies.autoload_paths
+      ActiveSupport::Dependencies.autoload_paths << File.expand_path(File.join("..", "..", "..", "app", "controllers"), __FILE__)
+    else
+      ActiveSupport::Dependencies.autoload_paths = [File.expand_path(File.join("..", "..", "..", "app", "controllers"), __FILE__)]
+    end
   end
 
   if defined? ActionController::Routing

secure-headers.gemspec

@@ -19,6 +19,5 @@ Gem::Specification.new do |gem|
   gem.test_files    = gem.files.grep(%r{^(test|spec|features)/})
   gem.require_paths = ["lib"]
   gem.add_dependency "brwsr", ">= 1.1.1"
-  gem.add_dependency "activesupport", ">= 2.0"
   gem.add_development_dependency "rake"
 end

spec/spec_helper.rb

@@ -1,6 +1,5 @@
 require 'rubygems'
 require 'spork'
-require 'active_support'
 
 unless Spork.using_spork?
   require 'simplecov'