View handler field math expression - Unformat token value before evaluating expression.

I create a view with 2 numeric field (A and B), the I add new Global:Math expression (C) to it. I set value to field C use token replacements [field_a] - ['field_b']

Everything is ok until i format number (use comma thousand separator) and render field A as link. The field C return a incorrect value.
The problem is class views_handler_field_math simply use method floatval() to convert token value to float value , so it fail to convert formatted number to float value (http://cgit.drupalcode.org/views/tree/handlers/views_handler_field_math....)

I think we should unformat number for token value before evaluating expression.