hook: ensure stderr is flushed when an exception is raised, for test stability
Windows has had issues with output order in test-ssh-proto-unbundle.t[1] since
it was created a few weeks ago. Each of the problems occurred when an exception
was thrown out of the hook.
Now the only thing blocking D2720 is the fact that the "abort: ..." lines on
stderr are totally AWOL. I have no idea where there are.
[1] https://buildbot.mercurial-scm.org/builders/Win7%20x86_64%20hg%20tests/builds/541/steps/run-tests.py%20%28python%202.7.13%29/logs/stdio
{
// Enforcing
"eqeqeq" : true, // true: Require triple equals (===) for comparison
"forin" : true, // true: Require filtering for..in loops with obj.hasOwnProperty()
"freeze" : true, // true: prohibits overwriting prototypes of native objects such as Array, Date etc.
"nonbsp" : true, // true: Prohibit "non-breaking whitespace" characters.
"undef" : true, // true: Require all non-global variables to be declared (prevents global leaks)
// Environments
"browser" : true // Web Browser (window, document, etc)
}