Remove old warning method

lib/liquid/tags/for.rb

@@ -58,7 +58,6 @@ module Liquid
     end
 
     def render(context)
-      context.errors.concat(@warnings) if @warnings
       context.registers[:for] ||= Hash.new(0)
 
       collection = context[@collection_name]

lib/liquid/tags/if.rb

@@ -29,7 +29,6 @@ module Liquid
     end
 
     def render(context)
-      context.errors.concat(@warnings) if @warnings
       context.stack do
         @blocks.each do |block|
           if block.evaluate(context)

lib/liquid/variable.rb

@@ -87,7 +87,6 @@ module Liquid
 
     def render(context)
       return '' if @name.nil?
-      context.errors << @warning if @warning
       @filters.inject(context[@name]) do |output, filter|
         filterargs = []
         keyword_args = {}