Fix ActionMailer test broken in 99d54599

actionmailer/lib/action_mailer/base.rb

@@ -375,6 +375,11 @@ def initialize(method_name=nil, *args)
       process(method_name, *args) if method_name
     end
 
+    def process(*args) #:nodoc:
+      lookup_context.skip_default_locale!
+      super
+    end
+
     # Allows you to pass random and unusual headers to the new +Mail::Message+ object
     # which will add them to itself.
     # 

actionpack/lib/abstract_controller/rendering.rb

@@ -24,8 +24,7 @@ def locale
     end
 
     def locale=(value)
-      @i18n_config.locale = value
-      @lookup_context.update_details(:locale => @i18n_config.locale)
+      @lookup_context.locale = value
     end
   end
 

actionpack/lib/action_view/lookup_context.rb

@@ -58,7 +58,7 @@ def initialize
 
     def initialize(view_paths, details = {})
       @details, @details_key = { :handlers => default_handlers }, nil
-      @frozen_formats = false
+      @frozen_formats, @skip_default_locale = false, false
       self.view_paths = view_paths
       self.update_details(details, true)
     end
@@ -147,7 +147,13 @@ def formats=(value)
         super(value)
       end
 
-      # Overload locale to return a symbol instead of array
+      # Do not use the default locale on template lookup.
+      def skip_default_locale!
+        @skip_default_locale = true
+        self.locale = nil
+      end
+
+      # Overload locale to return a symbol instead of array.
       def locale
         @details[:locale].first
       end
@@ -160,7 +166,8 @@ def locale=(value)
           config = I18n.config.respond_to?(:i18n_config) ? I18n.config.i18n_config : I18n.config
           config.locale = value
         end
-        super(_locale_defaults)
+
+        super(@skip_default_locale ? I18n.locale : _locale_defaults)
       end
 
       # Update the details keys by merging the given hash into the current