saml: allow to keep existing roles on login (#3440)

src/Configuration/SamlConfiguration.php

@@ -46,6 +46,11 @@ final class SamlConfiguration implements SamlConfigurationInterface
         return $this->configuration->getSamlRolesMapping();
     }
 
+    public function isRolesResetOnLogin(): bool
+    {
+        return $this->configuration->isSamlRolesResetOnLogin();
+    }
+
     public function getConnection(): array
     {
         return $this->configuration->getSamlConnection();

src/Configuration/SamlConfigurationInterface.php

@@ -21,5 +21,7 @@ interface SamlConfigurationInterface
 
     public function getRolesMapping(): array;
 
+    public function isRolesResetOnLogin(): bool;
+
     public function getConnection(): array;
 }

src/Configuration/SystemConfiguration.php

@@ -86,6 +86,11 @@ class SystemConfiguration implements SystemBundleConfiguration
         return (array) $this->find('saml.roles.mapping');
     }
 
+    public function isSamlRolesResetOnLogin(): bool
+    {
+        return (bool) $this->find('saml.roles.resetOnLogin');
+    }
+
     public function getSamlConnection(): array
     {
         return (array) $this->find('saml.connection');