GUACAMOLE-96: Add API support for augmenting functionality of other extensions.

extensions/guacamole-auth-cas/src/main/java/org/apache/guacamole/auth/cas/CASAuthenticationProvider.java

@@ -107,6 +107,13 @@ public class CASAuthenticationProvider implements AuthenticationProvider {
 
     }
 
+    @Override
+    public UserContext decorate(UserContext context,
+            AuthenticatedUser authenticatedUser, Credentials credentials)
+            throws GuacamoleException {
+        return context;
+    }
+
     @Override
     public void shutdown() {
         // Do nothing

extensions/guacamole-auth-duo/src/main/java/org/apache/guacamole/auth/duo/DuoAuthenticationProvider.java

@@ -102,6 +102,13 @@ public class DuoAuthenticationProvider implements AuthenticationProvider {
         return context;
     }
 
+    @Override
+    public UserContext decorate(UserContext context,
+            AuthenticatedUser authenticatedUser, Credentials credentials)
+            throws GuacamoleException {
+        return context;
+    }
+
     @Override
     public void shutdown() {
         // Do nothing

extensions/guacamole-auth-header/src/main/java/org/apache/guacamole/auth/header/HTTPHeaderAuthenticationProvider.java

@@ -107,6 +107,13 @@ public class HTTPHeaderAuthenticationProvider implements AuthenticationProvider
 
     }
 
+    @Override
+    public UserContext decorate(UserContext context,
+            AuthenticatedUser authenticatedUser, Credentials credentials)
+            throws GuacamoleException {
+        return context;
+    }
+
     @Override
     public void shutdown() {
         // Do nothing

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/apache/guacamole/auth/jdbc/InjectedAuthenticationProvider.java

@@ -104,6 +104,13 @@ public abstract class InjectedAuthenticationProvider implements AuthenticationPr
                 authenticatedUser, credentials);
     }
 
+    @Override
+    public UserContext decorate(UserContext context,
+            AuthenticatedUser authenticatedUser, Credentials credentials)
+            throws GuacamoleException {
+        return context;
+    }
+
     @Override
     public void shutdown() {
         // Do nothing

extensions/guacamole-auth-ldap/src/main/java/org/apache/guacamole/auth/ldap/LDAPAuthenticationProvider.java

@@ -103,6 +103,13 @@ public class LDAPAuthenticationProvider implements AuthenticationProvider {
         return context;
     }
 
+    @Override
+    public UserContext decorate(UserContext context,
+            AuthenticatedUser authenticatedUser, Credentials credentials)
+            throws GuacamoleException {
+        return context;
+    }
+
     @Override
     public void shutdown() {
         // Do nothing

extensions/guacamole-auth-openid/src/main/java/org/apache/guacamole/auth/openid/OpenIDAuthenticationProvider.java

@@ -107,6 +107,13 @@ public class OpenIDAuthenticationProvider implements AuthenticationProvider {
 
     }
 
+    @Override
+    public UserContext decorate(UserContext context,
+            AuthenticatedUser authenticatedUser, Credentials credentials)
+            throws GuacamoleException {
+        return context;
+    }
+
     @Override
     public void shutdown() {
         // Do nothing