push key checking up

We should disconnect `array_of_permitted_scalars_filter` from the
instance so that we can make hash filtering functional.  For now, pull
the conditional up out of that method

Author: tenderlove

actionpack/lib/action_controller/metal/strong_parameters.rb

@@ -649,7 +649,7 @@ def array_of_permitted_scalars?(value)
       end
 
       def array_of_permitted_scalars_filter(params, key)
-        if has_key?(key) && array_of_permitted_scalars?(self[key])
+        if array_of_permitted_scalars?(self[key])
           params[key] = self[key]
         end
       end
@@ -661,6 +661,7 @@ def hash_filter(params, filter)
         # Slicing filters out non-declared keys.
         slice(*filter.keys).each do |key, value|
           next unless value
+          next unless has_key? key
 
           if filter[key] == EMPTY_ARRAY
             # Declaration { comment_ids: [] }.