RFR: 8299829: In jshell, the output of "0".repeat(49999)+"2" ends with a '0' [v2]

[Adam Sotona]

> "0".repeat(49999)+"2" correctly evaluates to a string with a terminating '2'. 
> However, jshell outputs it with a terminating '0'.
> 
> Jshell provides double truncation of long Strings. 
> One is performed in jdk.jshell.execution.ExecutionControlForwarder to fit into MAX_UTF_CHARS = 21844 (which is exactly the point where "2" disappears). 
> Second truncation is performed in jdk.internal.jshell.tool.Feedback to fit presentation requirements. 
> While ExecutionControlForwarder truncates right part of the String, Feedback truncated inner part in 2/3 and joins the parts with " ... ". 
> 
> Proposed patch fixes ExecutionControlForwarder to truncate long Strings the same way as Feedback, so the right part of any long String won't disappear and double or repeated truncation provides consistent results.
> 
> Please review :)
> 
> Thanks,
> Adam

Adam Sotona has updated the pull request incrementally with one additional commit since the last revision:

  added test

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/11927/files
  - new: https://git.openjdk.org/jdk/pull/11927/files/d6ff2bf2..6f014b6c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=11927&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=11927&range=00-01

  Stats: 3 lines in 1 file changed: 1 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/11927.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11927/head:pull/11927

PR: https://git.openjdk.org/jdk/pull/11927