ruby 1.9 and utf8 erb templates

First patch:

irb(main):001:0> require 'erb'
=> true
irb(main):002:0> puts ERB.new('test').src
#coding:UTF-8
_erbout = ''; _erbout.concat "test"; _erbout.force_encoding(__ENCODING__)
=> nil

it forces encoding to ENCODING. ENCODING equals encoding of ruby file that executes that code. And in Rails this code is executed by actionpack/lib/action_view/renderable.rb.

Second patch:

-          headers["Content-Length"] = body.size.to_s
+          headers["Content-Length"] = (body.respond_to?(:bytesize) ? body.bytesize : body.size).to_s

Content-length needs size in bytes, not in chars, so for 1.9 .size no longer valid.