Simplify construction of Jackson XML mapper slightly (for test wrt issue 396); update release notes wrt 2.12.0

Author: cowtowncoder

release-notes/VERSION-2.x

@@ -16,14 +16,14 @@ Co-maintainers:
 
 2.12.1 (not yet released)
 
-#356: Serialization of inline classes under Kotlin 1.4+
 #402: Remove implicitly-included `java.base` dep in `module-info.java`
  (reported by UkonnRa@github)
 
 2.12.0 (29-Nov-2020)
 
 #322: Added extension methods to SimpleModule addSerializer and addDeserializer to support KClass arguments
     that register the serializer/deserializer for both the java type and java class.
+#356: Kotlin 1.4 support
 #385: Add Moditect, source module info, to allow Kotlin module usage with Java Module system
 - Add Gradle Module Metadata (https://blog.gradle.org/alignment-with-gradle-module-metadata)
 

src/test/kotlin/com/fasterxml/jackson/module/kotlin/test/failing/Github396.kt

@@ -1,10 +1,7 @@
 package com.fasterxml.jackson.module.kotlin.test.failing
 
-import com.fasterxml.jackson.dataformat.xml.JacksonXmlModule
-import com.fasterxml.jackson.dataformat.xml.XmlFactory
 import com.fasterxml.jackson.dataformat.xml.XmlMapper
 import com.fasterxml.jackson.module.kotlin.registerKotlinModule
-import javax.xml.stream.XMLInputFactory
 import kotlin.test.Test
 import kotlin.test.assertEquals
 
@@ -15,8 +12,7 @@ class TestGithub396 {
      */
     @Test
     fun testMissingConstructor() {
-        val factory = XmlFactory(XMLInputFactory.newInstance())
-        val mapper = XmlMapper(factory, JacksonXmlModule()).registerKotlinModule()
+        val mapper = XmlMapper().registerKotlinModule()
 
         val xml = "<product><stuff></stuff></product>"
         val product: Product = mapper.readValue(xml, Product::class.java)