RFR: 8249783: Simplify DerValue and DerInputStream [v4]

[Weijun Wang]

> This code change rewrites DerValue into a mostly immutable class and simplifies DerInputStream as a wrapper for a
> series of DerValues objects. DerInputBuffer is removed.
> All existing methods of DerValue and DerInputStream should still work with the exact same behavior, except for a few
> places where bugs are fixed. For example, Indefinite length must be used with a constructed tag.
> Except for the ObjectIdentifier class where DerInputBuffer is directly referenced, no other code is touched.

Weijun Wang has updated the pull request incrementally with one additional commit since the last revision:

  some small tuning

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/232/files
  - new: https://git.openjdk.java.net/jdk/pull/232/files/ac77172e..23205637

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=232&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=232&range=02-03

  Stats: 26 lines in 2 files changed: 4 ins; 11 del; 11 mod
  Patch: https://git.openjdk.java.net/jdk/pull/232.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/232/head:pull/232

PR: https://git.openjdk.java.net/jdk/pull/232