XYZ-37: Advanced Permissions Phase 1 Backend. (#8159)

* XYZ-13: Update Permission and Role structs to new design.

* XYZ-10: Role store.

* XYZ-9/XYZ-44: Roles API endpoints and WebSocket message.

* XYZ-8: Switch server permissions checks to store backed roles.

* XYZ-58: Proper validation of roles where required.

* XYZ-11/XYZ-55: Migration to store backed roles from policy config.

* XYZ-37: Update unit tests to work with database roles.

* XYZ-56: Remove the "guest" role.

* Changes to SetDefaultRolesFromConfig.

* Short-circuit the store if nothing has changed.

* Address first round of review comments.

* Address second round of review comments.

model/user.go

@@ -432,7 +432,7 @@ func IsValidUserRoles(userRoles string) bool {
 	roles := strings.Fields(userRoles)
 
 	for _, r := range roles {
-		if !isValidRole(r) {
+		if !IsValidRoleName(r) {
 			return false
 		}
 	}
@@ -445,11 +445,6 @@ func IsValidUserRoles(userRoles string) bool {
 	return true
 }
 
-func isValidRole(roleId string) bool {
-	_, ok := DefaultRoles[roleId]
-	return ok
-}
-
 // Make sure you acually want to use this function. In context.go there are functions to check permissions
 // This function should not be used to check permissions.
 func (u *User) IsInRole(inRole string) bool {