title: Integration test with rspec and devise sign_in env
body: <p>I am using devise configured to use omniauth facebook sign in integration.
  When calling the <code>sign_in</code> method from my <code>spec/request</code> tests I get:</p>
  
  <pre><code>undefined method `env' for nil:NilClass
  </code></pre>
  
  <p>spec:</p>
  
  <pre><code>describe FacebookController do
    include Devise::TestHelpers
  
    it "should display facebook logged in status" do
      @user = User.create(:id =&gt; "123", :token =&gt; "token")
      sign_in @user
      visit facebook_path
    end
  end
  </code></pre>