Increase OAuth2 state parameter limit

model/authorize.go

@@ -62,7 +62,7 @@ func (ad *AuthData) IsValid() *AppError {
 		return NewAppError("AuthData.IsValid", "model.authorize.is_valid.redirect_uri.app_error", nil, "client_id="+ad.ClientId, http.StatusBadRequest)
 	}
 
-	if len(ad.State) > 128 {
+	if len(ad.State) > 1024 {
 		return NewAppError("AuthData.IsValid", "model.authorize.is_valid.state.app_error", nil, "client_id="+ad.ClientId, http.StatusBadRequest)
 	}