[JENKINS-16845] Hotfix to at least allow the job to be loaded.

Root cause seems to be broken serial form of FingerprintAction, probably caused by lazy loading.

changelog.html

@@ -58,6 +58,9 @@ Upcoming changes</a>
   <li class=bug>
     JUnit result archiver should only fail builds if there are really no results - i.e. also no skipped tests.
     (<a href="https://issues.jenkins-ci.org/browse/JENKINS-7970">issue 7970</a>)
+  <li class='major bug'>
+      <code>NullPointerException</code> related to lazy loading when loading some builds using fingerprinting.
+    (<a href="https://issues.jenkins-ci.org/browse/JENKINS-16845">issue 16845</a>)
   <li class=rfe>
     Better display of parameters in queue items.
     (<a href="https://issues.jenkins-ci.org/browse/JENKINS-17454">issue 17454</a>)

core/src/main/java/hudson/tasks/Fingerprinter.java

@@ -294,7 +294,7 @@ public class Fingerprinter extends Recorder implements Serializable, DependencyD
      */
     public static final class FingerprintAction implements RunAction {
         
-        private final AbstractBuild build;
+        private AbstractBuild build;
 
         private static final Random rand = new Random();
 
@@ -343,6 +343,11 @@ public class Fingerprinter extends Recorder implements Serializable, DependencyD
         }
 
         public void onLoad() {
+            if (build.getParent() == null) {
+                logger.warning("JENKINS-16845: broken FingerprintAction record");
+                build = null;
+                return;
+            }
             // share data structure with nearby builds, but to keep lazy loading efficient,
             // don't go back the history forever.
             if (rand.nextInt(2)!=0) {
@@ -430,6 +435,11 @@ public class Fingerprinter extends Recorder implements Serializable, DependencyD
         public Map<AbstractProject,Integer> getDependencies(boolean includeMissing) {
             Map<AbstractProject,Integer> r = new HashMap<AbstractProject,Integer>();
 
+            if (build == null) {
+                // Broken, do not do anything.
+                return r;
+            }
+
             for (Fingerprint fp : getFingerprints().values()) {
                 BuildPtr bp = fp.getOriginal();
                 if(bp==null)    continue;       // outside Hudson

core/src/main/resources/hudson/tasks/Fingerprinter/FingerprintAction/index.jelly

@@ -30,7 +30,9 @@ THE SOFTWARE.
 <?jelly escape-by-default='true'?>
 <j:jelly xmlns:j="jelly:core" xmlns:st="jelly:stapler" xmlns:d="jelly:define" xmlns:l="/lib/layout" xmlns:t="/lib/hudson" xmlns:f="/lib/form">
   <l:layout>
-    <st:include it="${it.build}" page="sidepanel.jelly" />
+    <j:if test="${it.build != null}">
+      <st:include it="${it.build}" page="sidepanel.jelly"/>
+    </j:if> <!-- else broken -->
     <l:main-panel>
       <h1>
         <img src="${imagesURL}/48x48/fingerprint.png" alt="" height="48" width="48"/>