RFR: 8266250: WebSocketTest and WebSocketProxyTest call assertEquals(List<byte[]>, List<byte[]>) [v4]

[Daniel Fuchs]

> Please find here an almost trivial test fix that should improve diagnostic in case of failures. 
> It also avoids relying on an unspecified behavior of `Assert.assertEquals`.

Daniel Fuchs has updated the pull request incrementally with one additional commit since the last revision:

  Renamed /problem/ into /message/

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/3776/files
  - new: https://git.openjdk.java.net/jdk/pull/3776/files/22dc8060..165322c5

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3776&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3776&range=02-03

  Stats: 4 lines in 2 files changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3776.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3776/head:pull/3776

PR: https://git.openjdk.java.net/jdk/pull/3776