RFR [9] 8138978: Examine usages of sun.misc.IOUtils

[Chris Hegarty]

This primary motivation behind this bug [1] is the clearing out of
sun.misc, in preparation for JEP 260 [2].

sun.misc.IOUtils is a JDK internal convenience utility class that
provides a single method that offers bulk blocking InputStream read
semantics. In 9, java.io.InputStream has been retrofitted with two
methods that provide similar, but not quite the same, functionality,
readNBytes and readAllBytes, see JDK-8080835 [3]. 

There are a number of places where IOUtils can be replaced with the
appropriate supported API, readNBytes or readAllBytes. 

There are a number of places, mainly in the security implementation,
that required to read a specific number of bytes ( not to end of
stream ), where it is preferable to not preallocate the byte[] and
allow it to "grow" lazily, to be defensive against protocol errors.
These cases cannot use read[N|All]Bytes, so it makes sense to retain 
IOUtils but locate it in a package, sun.security.util, that makes it
clear who its primary consumer is.

http://cr.openjdk.java.net/~chegar/8138978/webrev.00/jdk/
http://cr.openjdk.java.net/~chegar/8138978/webrev.00/hotspot/

-Chris.

[1] https://bugs.openjdk.java.net/browse/JDK-8138978
[2] https://bugs.openjdk.java.net/browse/JDK-8132928
[3] https://bugs.openjdk.java.net/browse/JDK-8080835