RFR: 8371587: Final mapping lost in ProcSmapsParser::parse_next [v2]

[Albert Mingkun Yang]

> A simple fix for off-by-one error in parsing `smaps` -- the final mapping is never recorded as we exits the parsing loop too early.
> 
> The spec of `parse_next` is updated to reflects what its caller expects. The newly added gtest fails without this path.
> 
> 
> Test: tier1

Albert Mingkun Yang has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision:

 - copyright-header
 - review
 - Merge branch 'master' into smap-parser
 - smap-parser

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/28225/files
  - new: https://git.openjdk.org/jdk/pull/28225/files/f79c046f..c179ccd5

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=28225&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=28225&range=00-01

  Stats: 73896 lines in 1020 files changed: 49098 ins; 18058 del; 6740 mod
  Patch: https://git.openjdk.org/jdk/pull/28225.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28225/head:pull/28225

PR: https://git.openjdk.org/jdk/pull/28225