[8u][RFR][2/3] 8157069: Assorted ZipFile improvements

[Taylor, Ben]

Hello,

This backport is a companion to 8145260 and should be followed by the backport
of 6233323, and is included for performance.

The patch was modified to remove changes to SignatureFileVerifier.java
These changes are already present from
8176536: Improved algorithm constraints checking[1][2].

Since this patch does not impact behavior, it does not include a test.

https://bugs.openjdk.java.net/browse/JDK-8157069
http://cr.openjdk.java.net/~cverghese/webrevs/8157069/webrev/

Thanks,
--Ben

[1] https://bugs.openjdk.java.net/browse/JDK-8176536
[2] http://hg.openjdk.java.net/jdk8u/jdk8u-dev/jdk/rev/cc7f20a9beb2