Rename session_class method to adapter_class

lib/webrat/core/methods.rb

@@ -20,7 +20,7 @@ module Webrat
     end
 
     def webrat_adapter
-      @_webrat_adapter ||= Webrat.session_class.new(self)
+      @_webrat_adapter ||= Webrat.adapter_class.new(self)
     end
 
     # all of these methods delegate to the @session, which should

lib/webrat/core/session.rb

@@ -12,7 +12,7 @@ module Webrat
   class InfiniteRedirectError < WebratError
   end
 
-  def self.session_class
+  def self.adapter_class
     case Webrat.configuration.mode
     when :rails
       RailsSession

spec/fakes/test_session.rb

@@ -1,5 +1,5 @@
 module Webrat #:nodoc:
-  def self.session_class #:nodoc:
+  def self.adapter_class #:nodoc:
     TestSession
   end