RFR: 8357862: Java argument file is parsed unexpectedly with trailing comment [v2]

[Christian Stein]

> Please review this fix to correctly parse tokens in an argument file that contains trailing comments without preceding whitespace characters before the '#' comment marker, the number sign.
> 
> The specifaction of the `java` Command has in section [java Command-Line Argument Files](https://docs.oracle.com/en/java/javase/12/docs/specs/man/java.html#java-command-line-argument-files):
> 
> Use the number sign `#` in the argument file to identify comments.
> All characters following the `#` are ignored until the end of line.
> 
> There is not requirement specified to prepend a comment in a line with at least one argument with one or more preceding whitespace characters.

Christian Stein has updated the pull request incrementally with one additional commit since the last revision:

  Extract shared function to compute current token

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/25589/files
  - new: https://git.openjdk.org/jdk/pull/25589/files/21afeb37..bea8cc79

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25589&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25589&range=00-01

  Stats: 31 lines in 1 file changed: 13 ins; 14 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/25589.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25589/head:pull/25589

PR: https://git.openjdk.org/jdk/pull/25589