module ActionView::Context

def _layout_for(name = nil)

overwritten by helpers to add more behavior.
returns the correct buffer on +yield+. This is usually
Encapsulates the interaction with the view flow so it 
def _layout_for(name = nil)
  name ||= :layout
  view_flow.get(name).html_safe
end

def _prepare_context

Prepares the context by setting the appropriate instance variables. 
def _prepare_context
  @view_flow     = OutputFlow.new
  @output_buffer = nil
  @virtual_path  = nil
end