deprecate the env method on controller instances

people should be accessing request information through the request
object, not via the env hash.  If they really really want at the env
hash, then they can get it off the request.

actionpack/lib/action_controller/metal.rb

 require 'active_support/core_ext/array/extract_options'
 require 'action_dispatch/middleware/stack'
+require 'active_support/deprecation'
 
 module ActionController
   # Extend ActionDispatch middleware stack to make it aware of options
@@ -119,6 +120,7 @@ class Metal < AbstractController::Base
     def env
       @_request.env
     end
+    deprecate :env
 
     # Returns the last part of the controller's name, underscored, without the ending
     # <tt>Controller</tt>. For instance, PostsController returns <tt>posts</tt>.

actionpack/lib/action_controller/metal/streaming.rb

@@ -199,7 +199,7 @@ module Streaming
       def _process_options(options) #:nodoc:
         super
         if options[:stream]
-          if env["HTTP_VERSION"] == "HTTP/1.0"
+          if request.version == "HTTP/1.0"
             options.delete(:stream)
           else
             headers["Cache-Control"] ||= "no-cache"

actionpack/lib/action_dispatch/http/request.rb

@@ -35,7 +35,7 @@ class Request < Rack::Request
         HTTP_ACCEPT HTTP_ACCEPT_CHARSET HTTP_ACCEPT_ENCODING
         HTTP_ACCEPT_LANGUAGE HTTP_CACHE_CONTROL HTTP_FROM
         HTTP_NEGOTIATE HTTP_PRAGMA HTTP_CLIENT_IP
-        HTTP_X_FORWARDED_FOR
+        HTTP_X_FORWARDED_FOR HTTP_VERSION
         ].freeze
 
     ENV_METHODS.each do |env|