title: Rails5 migration: can't quote Array
body: <p>I try to migrate my app from Rails 4 to Rails 5
  Here is my migration:</p>
  
  <pre><code>class AddRevealedIdsToUser &lt; ActiveRecord::Migration[5.0]
    def change
      add_column :users, :revealed_ids, :text, default: []
    end
  end
  </code></pre>
  
  <p>And model:</p>
  
  <pre><code>serialize :revealed_ids
  </code></pre>
  
  <p>It worked perfectly in Rails 4, now I have an error:</p>
  
  <pre><code>== 20160416214334 AddRevealedIdsToUser: migrating =============================
  -- add_column(:users, :revealed_ids, :text, {:default=&gt;[]})
  rails aborted!
  StandardError: An error has occurred, this and all later migrations canceled:
  
  can't quote Array
  /usr/local/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/quoting.rb:177:in `_quote'
  /usr/local/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/postgresql/quoting.rb:96:in `_quote'
  </code></pre>
  
  <p>how to solve?</p>