bug#15461: 24.3; exec-path on ms windows should contain current directory

[Jarek Czekalski]

> If we extend the issue to how executables are found
> by call-process, cmdproxy, shell-command, etc., we will just add
> unneeded complexity.

This remark is unnecessary. You already said that "call-process" on 
Windows should not find the executables in the current buffer's 
directory. That's the argument and that's enough. Saying about "unneeded 
complexity" only makes me think that you want to close the bug as 
quickly as possible, without much thinking.

> Again, let's stay focused on completion.

Agreed. I will provide a completion-only patch.

Jarek