RFR(XS): 8197972: Always verify non-system classes during CDS dump time

[Calvin Cheung]

JBS: https://bugs.openjdk.java.net/browse/JDK-8197972

CSR: https://bugs.openjdk.java.net/browse/JDK-8198849

webrev: http://cr.openjdk.java.net/~ccheung/8197972/webrev.00/

This change is to default -Xverify to remote during CDS dumping.
If the user specifies -Xverify:none during CDS dumping, the following 
message will be printed.

bash-4.2$ $MYJDK/bin/java -Xverify:none -Xlog:cds -Xshare:dump
[0.003s][info][cds] All non-system classes will be verified 
(-Xverify:remote) during CDS dump time.

The change passed hs-tier1, hs-tier2, and hs-tier3 tests.

thanks,
Calvin