Remove policy nesting errors (#7449)

Policy nesting has been supported for a while
now, we should remove references of code and
docs indicating nesting is not allowed anymore.

cmd/api-errors.go

@@ -184,7 +184,6 @@ const (
 	ErrStorageFull
 	ErrRequestBodyParse
 	ErrObjectExistsAsDirectory
-	ErrPolicyNesting
 	ErrInvalidObjectName
 	ErrInvalidResourceName
 	ErrServerNotInitialized
@@ -884,11 +883,6 @@ var errorCodes = errorCodeMap{
 		Description:    "Multiple disks failures, unable to write data.",
 		HTTPStatusCode: http.StatusServiceUnavailable,
 	},
-	ErrPolicyNesting: {
-		Code:           "XMinioPolicyNesting",
-		Description:    "New bucket policy conflicts with an existing policy. Please try again with new prefix.",
-		HTTPStatusCode: http.StatusConflict,
-	},
 	ErrInvalidObjectName: {
 		Code:           "XMinioInvalidObjectName",
 		Description:    "Object name contains unsupported characters.",

cmd/object-api-errors.go

@@ -372,13 +372,6 @@ func (e NotImplemented) Error() string {
 	return "Not Implemented"
 }
 
-// PolicyNesting - policy nesting conflict.
-type PolicyNesting struct{}
-
-func (e PolicyNesting) Error() string {
-	return "New bucket policy conflicts with an existing policy. Please try again with new prefix."
-}
-
 // UnsupportedMetadata - unsupported metadata
 type UnsupportedMetadata struct{}
 

cmd/web-handlers.go

@@ -1840,8 +1840,6 @@ func toWebAPIError(err error) APIError {
 		return getAPIError(ErrWriteQuorum)
 	case InsufficientReadQuorum:
 		return getAPIError(ErrReadQuorum)
-	case PolicyNesting:
-		return getAPIError(ErrPolicyNesting)
 	case NotImplemented:
 		return APIError{
 			Code:           "NotImplemented",