Remove Mime::Type translations from Action View

Action View should not be responsible for translating mime types. Any
translation that's needed should be handled at controller level.

actionpack/lib/action_view/template.rb

@@ -121,7 +121,7 @@ def initialize(source, identifier, handler, details)
       @locals            = details[:locals] || []
       @virtual_path      = details[:virtual_path]
       @updated_at        = details[:updated_at] || Time.now
-      @formats           = Array(format).map { |f| f.is_a?(Mime::Type) ? f.ref : f }
+      @formats           = Array(format).map { |f| f.to_sym }
       @compile_mutex     = Mutex.new
     end
 
@@ -146,8 +146,8 @@ def render(view, locals, buffer=nil, &block)
       handle_render_error(view, e)
     end
 
-    def mime_type
-      @mime_type ||= Mime::Type.lookup_by_extension(@formats.first.to_s) if @formats.first
+    def type
+      @type ||= @formats.first.to_sym if @formats.first
     end
 
     # Receives a view object and return a template similar to self by using @virtual_path.

actionpack/lib/action_view/template/handlers/builder.rb

@@ -3,7 +3,7 @@ module Template::Handlers
     class Builder
       # Default format used by Builder.
       class_attribute :default_format
-      self.default_format = Mime::XML
+      self.default_format = :xml
 
       def call(template)
         require_engine

actionpack/lib/action_view/template/resolver.rb

@@ -235,7 +235,7 @@ def extract_handler_and_format(path, default_formats)
       extension = pieces.pop
       ActiveSupport::Deprecation.warn "The file #{path} did not specify a template handler. The default is currently ERB, but will change to RAW in the future." unless extension
       handler = Template.handler_for_extension(extension)
-      format  = pieces.last && Mime[pieces.last]
+      format  = pieces.last && pieces.last.to_sym
       [handler, format]
     end
   end

actionpack/lib/action_view/template/text.rb

@@ -2,12 +2,11 @@ module ActionView #:nodoc:
   # = Action View Text Template
   class Template
     class Text #:nodoc:
-      attr_accessor :mime_type
+      attr_accessor :type
 
-      def initialize(string, mime_type = nil)
-        @string      = string.to_s
-        @mime_type   = Mime[mime_type] || mime_type if mime_type
-        @mime_type ||= Mime::TEXT
+      def initialize(string, type = nil)
+        @string = string.to_s
+        @type = type || :text
       end
 
       def identifier
@@ -27,7 +26,7 @@ def render(*args)
       end
 
       def formats
-        [@mime_type.to_sym]
+        [@type.to_sym]
       end
     end
   end