[FIXED JENKINS-20442] Integrate annotation-indexer 1.6 with improved robustness.

changelog.html

@@ -55,6 +55,9 @@ Upcoming changes</a>
 <!-- Record your changes in the trunk here. -->
 <div id="trunk" style="display:none"><!--=TRUNK-BEGIN=-->
 <ul class=image>
+  <li class=bug>
+    Linkage error in <code>InitializerFinder.discoverTasks</code> blocks startup.
+    (<a href="https://issues.jenkins-ci.org/browse/JENKINS-20442">issue 20442</a>)
   <li class=rfe>
     Show different “up” link for jobs in folders.
     (<a href="https://issues.jenkins-ci.org/browse/JENKINS-20106">issue 20106</a>)

core/pom.xml

@@ -194,7 +194,7 @@ THE SOFTWARE.
     <dependency>
       <groupId>org.jenkins-ci</groupId>
       <artifactId>annotation-indexer</artifactId>
-      <version>1.5</version>
+      <version>1.6</version>
     </dependency>
     <dependency>
       <groupId>org.jenkins-ci</groupId>