8231202: Suppress warnings on non-serializable non-transient instance fields in serializable classes

Reviewed-by: rriggs, chegar

src/java.base/share/classes/java/time/Clock.java

@@ -641,6 +641,7 @@ public abstract class Clock {
     static final class OffsetClock extends Clock implements Serializable {
         @java.io.Serial
         private static final long serialVersionUID = 2007484719125426256L;
+        @SuppressWarnings("serial") // Not statically typed as Serializable
         private final Clock baseClock;
         private final Duration offset;
 
@@ -692,6 +693,7 @@ public abstract class Clock {
     static final class TickClock extends Clock implements Serializable {
         @java.io.Serial
         private static final long serialVersionUID = 6504659149906368850L;
+        @SuppressWarnings("serial") // Not statically typed as Serializable
         private final Clock baseClock;
         private final long tickNanos;
 

src/java.base/share/classes/java/time/chrono/ChronoPeriodImpl.java

@@ -109,6 +109,7 @@ final class ChronoPeriodImpl
     /**
      * The chronology.
      */
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private final Chronology chrono;
     /**
      * The number of years.