RFR: 8266571: Sequenced Collections [v2]

[Stuart Marks]

> PR for Sequenced Collections implementation.

Stuart Marks has updated the pull request incrementally with two additional commits since the last revision:

 - More specification tweaks.
 - Add simple overrides to ArrayList.

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Changes:
  - all: https://git.openjdk.org/jdk/pull/7387/files
  - new: https://git.openjdk.org/jdk/pull/7387/files/31f7d102..500841de

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=7387&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=7387&range=00-01

  Stats: 155 lines in 10 files changed: 110 ins; 13 del; 32 mod
  Patch: https://git.openjdk.org/jdk/pull/7387.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/7387/head:pull/7387

PR: https://git.openjdk.org/jdk/pull/7387