Merge pull request #2621 from icco/master

Issue with schema dump

activerecord/lib/active_record/schema_dumper.rb

@@ -40,7 +40,7 @@ def initialize(connection)
       def header(stream)
         define_params = @version ? ":version => #{@version}" : ""
 
-        if stream.respond_to?(:external_encoding)
+        if stream.respond_to?(:external_encoding) && stream.external_encoding
           stream.puts "# encoding: #{stream.external_encoding.name}"
         end