ICU-22202 Extended the code to do the right thing for all the valid "…

…year" characters.

icu4j/main/core/src/main/java/com/ibm/icu/text/DateIntervalFormat.java

@@ -2314,8 +2314,8 @@ private static boolean fieldExistsInSkeleton(int field, String skeleton)
                 // if the caller specified Calendar.MONTH, check the pattern for both M and L
                 result = skeleton.contains("L");
             } else if (fieldChar.equals("y")) {
-                // if the caller specified Calendar.YEAR, check the pattern for both y and U
-                result = skeleton.contains("U");
+                // if the caller specified Calendar.YEAR, check the pattern for y, Y, u, U, and r
+                result = skeleton.contains("U") || skeleton.contains("Y") || skeleton.contains("u") || skeleton.contains("r");
             }
         }
         return result;