If a proposal is heretofore or hereafter made to dedicate real property for public improvement, there is a conclusive presumption that the proposed dedication was not accepted if all of the following conditions are satisfied:

1. (a) The proposal was made by filing a map only.
2. (b) No acceptance of the dedication was made and recorded within 25 years after the map was filed.
3. (c) The real property was not used for the purpose for which the dedication was proposed within 25 years after the map was filed.
4. (d) The real property was sold to a third person after the map was filed and used as if free of the dedication.