OO-1593: score can always be null

src/main/java/org/olat/course/run/scoring/ScoreAccounting.java

@@ -200,7 +200,11 @@ public class ScoreAccounting {
 						.createAssessmentEntry(cNode, assessedIdentity, se);
 					changes = true;
 				} else if(!same(se, entry)) {
-					entry.setScore(new BigDecimal(score));
+					if(score != null) {
+						entry.setScore(new BigDecimal(score));
+					} else {
+						entry.setScore(null);
+					}
 					entry.setPassed(passed);
 					entry = userCourseEnvironment.getCourseEnvironment().getAssessmentManager().updateAssessmentEntry(entry);
 					identToEntries.put(cNode.getIdent(), entry);

src/main/java/org/olat/upgrade/OLATUpgrade_11_0_0.java

@@ -256,7 +256,7 @@ public class OLATUpgrade_11_0_0 extends OLATUpgrade {
 			if(!identityKeys.contains(identity.getKey())) {
 				AssessmentEntry entry = createAssessmentEntry(identity, null, course, courseEntry, rootNode.getIdent());
 				if(statement.getScore() != null) {
-					entry.setScore(new BigDecimal(statement.getScore().floatValue()));
+					entry.setScore(new BigDecimal(statement.getScore()));
 				}
 				if(statement.getPassed() != null) {
 					entry.setPassed(statement.getPassed());