Fix Kotlin bean w/ default + secondary ctors handling

This commit polishes SPR-16022 fix in order to handle correctly
the case when primary and default constructors are the same when
a secondary constructor is defined.

Issue: SPR-16289

Author: sdeleuze

spring-beans/src/main/java/org/springframework/beans/factory/annotation/AutowiredAnnotationBeanPostProcessor.java

@@ -347,7 +347,8 @@ else if (candidates.size() == 1 && logger.isWarnEnabled()) {
 					else if (rawCandidates.length == 1 && rawCandidates[0].getParameterCount() > 0) {
 						candidateConstructors = new Constructor<?>[] {rawCandidates[0]};
 					}
-					else if (nonSyntheticConstructors == 2 && primaryConstructor != null && defaultConstructor != null) {
+					else if (nonSyntheticConstructors == 2 && primaryConstructor != null
+							&& defaultConstructor != null && !primaryConstructor.equals(defaultConstructor)) {
 						candidateConstructors = new Constructor<?>[] {primaryConstructor, defaultConstructor};
 					}
 					else if (nonSyntheticConstructors == 1 && primaryConstructor != null) {

spring-beans/src/test/kotlin/org/springframework/beans/factory/annotation/KotlinAutowiredTests.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2018 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -169,6 +169,20 @@ class KotlinAutowiredTests {
 		assertEquals(tb, kb.testBean)
 	}
 
+	@Test  // SPR-16289
+	fun `Instantiation via secondary constructor when a default primary is defined`() {
+		val bf = DefaultListableBeanFactory()
+		val bpp = AutowiredAnnotationBeanPostProcessor()
+		bpp.setBeanFactory(bf)
+		bf.addBeanPostProcessor(bpp)
+		val bd = RootBeanDefinition(KotlinBeanWithPrimaryAndSecondaryConstructors::class.java)
+		bd.scope = RootBeanDefinition.SCOPE_PROTOTYPE
+		bf.registerBeanDefinition("bean", bd)
+
+		bf.getBean(KotlinBeanWithPrimaryAndSecondaryConstructors::class.java, "foo")
+		bf.getBean(KotlinBeanWithPrimaryAndSecondaryConstructors::class.java)
+	}
+
 	@Test(expected = BeanCreationException::class)  // SPR-16022
 	fun `No autowiring with primary and secondary non annotated constructors`() {
 		val bf = DefaultListableBeanFactory()
@@ -244,6 +258,11 @@ class KotlinAutowiredTests {
 		constructor() : this(TestBean())
 	}
 
+	@Suppress("unused", "UNUSED_PARAMETER")
+	class KotlinBeanWithPrimaryAndSecondaryConstructors() {
+		constructor(p: String) : this()
+	}
+
 	class KotlinBeanWithSecondaryConstructor(
 			val optional: String = "foo",
 			val injectedFromConstructor: TestBean