CLDR-17851 update per review comments

- roll by 2 days instead of one

Author: srl295

tools/cldr-code/src/main/java/org/unicode/cldr/test/ExampleGenerator.java

@@ -3144,12 +3144,13 @@ private void handleEras(XPathParts parts, String value, List<String> examples) {
         if (startCal == null && prevEra != null && prevEra.getEnd() != null) {
             startCal = prevEra.getEndCalendar();
             // shift forward so we are in the next era
-            startCal.setTimeInMillis(startCal.getTimeInMillis() + (DateConstants.MILLIS_PER_DAY));
+            startCal.setTimeInMillis(
+                    startCal.getTimeInMillis() + DateConstants.MILLIS_PER_TWO_DAYS);
         }
         if (endCal == null && nextEra != null && nextEra.getStart() != null) {
             endCal = nextEra.getStartCalendar();
             // shift backward so we are in the prev era
-            endCal.setTimeInMillis(endCal.getTimeInMillis() - (DateConstants.MILLIS_PER_DAY));
+            endCal.setTimeInMillis(endCal.getTimeInMillis() - DateConstants.MILLIS_PER_TWO_DAYS);
         }
 
         GregorianCalendar sampleDate = null;
@@ -3158,18 +3159,18 @@ private void handleEras(XPathParts parts, String value, List<String> examples) {
             // roll back a day to not hit the edge
             sampleDate = endCal;
             sampleDate.setTimeInMillis(
-                    sampleDate.getTimeInMillis() - (DateConstants.MILLIS_PER_DAY));
+                    sampleDate.getTimeInMillis() - DateConstants.MILLIS_PER_TWO_DAYS);
         } else if (startCal == null && endCal != null) {
             // roll back a day to not hit the edge
             sampleDate = endCal;
             sampleDate.setTimeInMillis(
-                    sampleDate.getTimeInMillis() - (DateConstants.MILLIS_PER_DAY));
+                    sampleDate.getTimeInMillis() - DateConstants.MILLIS_PER_TWO_DAYS);
         } else if (startCal != null && endCal == null) {
             sampleDate = new GregorianCalendar(2002, 6, 15); // CLDR repo root commit
             if (sampleDate.before(startCal)) {
                 sampleDate = startCal;
                 sampleDate.setTimeInMillis(
-                        sampleDate.getTimeInMillis() + (DateConstants.MILLIS_PER_DAY));
+                        sampleDate.getTimeInMillis() + DateConstants.MILLIS_PER_TWO_DAYS);
             }
         } else {
             // System.err.println("No good date for " + eraData);

tools/cldr-code/src/main/java/org/unicode/cldr/util/DateConstants.java

@@ -15,6 +15,7 @@ public class DateConstants {
     public static final long MILLIS_PER_MINUTE = MILLIS_PER_SECOND * 60;
     public static final long MILLIS_PER_HOUR = MILLIS_PER_MINUTE * 60;
     public static final long MILLIS_PER_DAY = MILLIS_PER_HOUR * 24;
+    public static final long MILLIS_PER_TWO_DAYS = 2 * MILLIS_PER_DAY;
     public static final long MILLIS_PER_MONTH = MILLIS_PER_DAY * 30;
 
     private static final Date getRecentHistory(Date d) {