Web api windows authentication custom role provider not working?

I added the following steps in a working web api project (VS 2015), The code can be viewed in http://stackoverflow.com/questions/32340902/web-api-windows-authentication-custom-role-provider-not-working-doesnt-hit-th

1. Create tables for roles, roleMembers and use code first to create all the data access code

2. Create a custom role provider class which inherit RoleProvider

3. Update the web.config file to use the custom role provicer

4. Decorate the control method with [Authorize(Roles ="ATestRole"]

I added the break points to following methods in the custom role provider but none of them were hit.

GetRolesForUser

IsUserInRole