Upgrade to Rails 2.2.0

As a side benefit, fix an (non-user-visible) bug in display_s5().
Also fixed a bug where removing orphaned pages did not expire cached summary pages.

vendor/rails/actionpack/lib/action_view/renderable_partial.rb

@@ -0,0 +1,48 @@
+module ActionView
+  # NOTE: The template that this mixin is being included into is frozen
+  # so you cannot set or modify any instance variables
+  module RenderablePartial #:nodoc:
+    extend ActiveSupport::Memoizable
+
+    def variable_name
+      name.sub(/\A_/, '').to_sym
+    end
+    memoize :variable_name
+
+    def counter_name
+      "#{variable_name}_counter".to_sym
+    end
+    memoize :counter_name
+
+    def render(view, local_assigns = {})
+      if defined? ActionController
+        ActionController::Base.benchmark("Rendered #{path_without_format_and_extension}", Logger::DEBUG, false) do
+          super
+        end
+      else
+        super
+      end
+    end
+
+    def render_partial(view, object = nil, local_assigns = {}, as = nil)
+      object ||= local_assigns[:object] ||
+        local_assigns[variable_name]
+
+      if view.respond_to?(:controller)
+        ivar = :"@#{variable_name}"
+        object ||=
+          if view.controller.instance_variable_defined?(ivar)
+            ActiveSupport::Deprecation::DeprecatedObjectProxy.new(
+              view.controller.instance_variable_get(ivar),
+              "#{ivar} will no longer be implicitly assigned to #{variable_name}")
+          end
+      end
+
+      # Ensure correct object is reassigned to other accessors
+      local_assigns[:object] = local_assigns[variable_name] = object
+      local_assigns[as] = object if as
+
+      render_template(view, local_assigns)
+    end
+  end
+end