Remove now unnecessary squash_instance_assigns_with_environments

Since it was just there to make sure instance assigns were overriden
when rending more than once with the same template instance.  It is
no longer necessary because the template no longer stores instance_assigns
which need to be overriden.

lib/liquid/context.rb

@@ -34,7 +34,6 @@ module Liquid
       @strict_variables    = false
       @resource_limits     = resource_limits || ResourceLimits.new(Template.default_resource_limits)
       @base_scope_depth    = 0
-      squash_instance_assigns_with_environments
 
       self.exception_renderer = Template.default_exception_renderer
       if rethrow_errors
@@ -246,16 +245,5 @@ module Liquid
     rescue Liquid::InternalError => exc
       exc
     end
-
-    def squash_instance_assigns_with_environments
-      @scopes.last.each_key do |k|
-        @environments.each do |env|
-          if env.key?(k)
-            scopes.last[k] = lookup_and_evaluate(env, k)
-            break
-          end
-        end
-      end
-    end # squash_instance_assigns_with_environments
   end # Context
 end # Liquid