convert more backend code from cask_name to token

missed in #7673

lib/cask/utils.rb

@@ -150,18 +150,18 @@ def self.file_is_descendant(file, dir)
     return false
   end
 
-  def self.method_missing_message(method, cask_name, section=nil)
+  def self.method_missing_message(method, token, section=nil)
     during = section ? "during #{section} " : '';
     poo = <<-EOPOO.undent
-      Unexpected method '#{method}' called #{during}on Cask #{cask_name}.
+      Unexpected method '#{method}' called #{during}on Cask #{token}.
 
-        If you are working on #{cask_name}, this may point to a typo. Otherwise
+        If you are working on #{token}, this may point to a typo. Otherwise
         it probably means this Cask is using a new feature. If that feature
         has been released, running
 
           brew update && brew upgrade brew-cask && brew cleanup && brew cask cleanup
 
-        should fix it. Otherwise you should wait to use #{cask_name} until the
+        should fix it. Otherwise you should wait to use #{token} until the
         new feature is released.
     EOPOO
     poo.split("\n").each { |line| opoo line }