[PATCH 1 of 4] worker: fix missed break on successful waitpid()

[Yuya Nishihara]

# HG changeset patch
# User Yuya Nishihara <yuya at tcha.org>
# Date 1479386581 -32400
#      Thu Nov 17 21:43:01 2016 +0900
# Node ID 9aef387fa3c32f92a8fc96088bad8c3de4e95aab
# Parent  854190becacb8abecddddbf5c18a777b02bbc045
worker: fix missed break on successful waitpid()

Follow-up for 5069a8a40b1b.

diff --git a/mercurial/worker.py b/mercurial/worker.py
--- a/mercurial/worker.py
+++ b/mercurial/worker.py
@@ -102,6 +102,7 @@ def _posixworker(ui, func, staticargs, a
             while True:
                 try:
                     p, st = os.waitpid(pid, (0 if blocking else os.WNOHANG))
+                    break
                 except OSError as e:
                     if e.errno == errno.EINTR:
                         continue