[JENKINS-10903] Serialize ImmutableList in the same manner as ImmutableMap.

This is a partial fix for JENKINS-10903. Any new builds will
be serialized correctly.

Based on ImmutableMapConverter.java

core/src/main/java/hudson/util/XStream2.java

@@ -23,6 +23,7 @@
  */
 package hudson.util;
 
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.thoughtworks.xstream.XStream;
 import com.thoughtworks.xstream.mapper.AnnotationMapper;
@@ -45,6 +46,7 @@ import jenkins.model.Jenkins;
 import hudson.model.Label;
 import hudson.model.Result;
 import hudson.model.Saveable;
+import hudson.util.xstream.ImmutableListConverter;
 import hudson.util.xstream.ImmutableMapConverter;
 import hudson.util.xstream.MapperDelegate;
 
@@ -107,6 +109,7 @@ public class XStream2 extends XStream {
 
         registerConverter(new RobustCollectionConverter(getMapper(),getReflectionProvider()),10);
         registerConverter(new ImmutableMapConverter(getMapper(),getReflectionProvider()),10);
+        registerConverter(new ImmutableListConverter(getMapper(),getReflectionProvider()),10);
         registerConverter(new ConcurrentHashMapConverter(getMapper(),getReflectionProvider()),10);
         registerConverter(new CopyOnWriteMap.Tree.ConverterImpl(getMapper()),10); // needs to override MapConverter
         registerConverter(new DescribableList.ConverterImpl(getMapper()),10); // explicitly added to handle subtypes
@@ -124,6 +127,8 @@ public class XStream2 extends XStream {
             public String serializedClass(Class type) {
                 if (type != null && ImmutableMap.class.isAssignableFrom(type))
                     return super.serializedClass(ImmutableMap.class);
+                else if (type != null && ImmutableList.class.isAssignableFrom(type))
+                    return super.serializedClass(ImmutableList.class);
                 else
                     return super.serializedClass(type);
             }

core/src/main/java/hudson/util/xstream/ImmutableListConverter.java

@@ -0,0 +1,71 @@
+/*
+ * The MIT License
+ *
+ * Copyright (c) 2010, InfraDNA, Inc.
+ * Copyright (c) 2011, Richard Mortimer
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package hudson.util.xstream;
+
+import com.google.common.collect.ImmutableList;
+import com.thoughtworks.xstream.XStream;
+import com.thoughtworks.xstream.converters.UnmarshallingContext;
+import com.thoughtworks.xstream.converters.collections.CollectionConverter;
+import com.thoughtworks.xstream.converters.reflection.ReflectionProvider;
+import com.thoughtworks.xstream.converters.reflection.SerializableConverter;
+import com.thoughtworks.xstream.io.HierarchicalStreamReader;
+import com.thoughtworks.xstream.mapper.Mapper;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * {@link ImmutableList} should convert like a list, instead of via serialization.
+ *
+ * @author Kohsuke Kawaguchi
+ * @author Richard Mortimer
+ */
+public class ImmutableListConverter extends CollectionConverter {
+    private final SerializableConverter sc;
+
+    public ImmutableListConverter(XStream xs) {
+        this(xs.getMapper(),xs.getReflectionProvider());
+    }
+
+    public ImmutableListConverter(Mapper mapper, ReflectionProvider reflectionProvider) {
+        super(mapper);
+        sc = new SerializableConverter(mapper,reflectionProvider);
+    }
+
+    @Override
+    public boolean canConvert(Class type) {
+        return ImmutableList.class.isAssignableFrom(type);
+    }
+
+    @Override
+    public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
+        return ImmutableList.copyOf((List)super.unmarshal(reader, context));
+    }
+
+    @Override
+    protected Object createCollection(Class type) {
+        return new ArrayList();
+    }
+}