8230613: Better ASCII conversions

Reviewed-by: dfuchs, naoto, mschoene, rhalade

src/java.base/share/classes/sun/net/idn/Punycode.java

@@ -185,7 +185,7 @@ public final class Punycode {
         for(j=0; j<srcLength; ++j) {
             if(srcCPCount==MAX_CP_COUNT) {
                 /* too many input code points */
-                throw new IndexOutOfBoundsException();
+                throw new ParseException("Too many input code points", -1);
             }
             c=src.charAt(j);
             if(isBasic(c)) {