Adds prefab values for java.time.Clock

src/main/java/nl/jqno/equalsverifier/internal/prefabvalues/JavaApiPrefabValues.java

@@ -218,6 +218,12 @@ private void addDateTimeClasses() {
             new GregorianCalendar(2010, 7, 5),
             new GregorianCalendar(2010, 7, 4)
         );
+        addValues(
+            Clock.class,
+            Clock.systemUTC(),
+            Clock.system(ZoneId.of("-10")),
+            Clock.systemUTC()
+        );
         addValues(Date.class, new Date(0), new Date(1), new Date(0));
         addValues(
             DateFormat.class,

src/test/java/nl/jqno/equalsverifier/integration/extended_contract/JavaApiClassesTest.java

@@ -522,6 +522,7 @@ static final class Java8ApiClassesContainer {
         private final CompletableFuture<?> completableFuture;
         private final StampedLock stampedLock;
         private final Supplier<?> supplier;
+        private final Clock clock;
         private final Duration duration;
         private final Instant instant;
         private final MonthDay monthDay;
@@ -546,6 +547,7 @@ public Java8ApiClassesContainer(
             CompletableFuture<?> completableFuture,
             StampedLock stampedLock,
             Supplier<?> supplier,
+            Clock clock,
             Duration duration,
             Instant instant,
             MonthDay monthDay,
@@ -569,6 +571,7 @@ public Java8ApiClassesContainer(
             this.completableFuture = completableFuture;
             this.stampedLock = stampedLock;
             this.supplier = supplier;
+            this.clock = clock;
             this.duration = duration;
             this.instant = instant;
             this.monthDay = monthDay;