loop.child is not defined on win32; take it out of ILoop there too.

src/gevent/_interfaces.py

@@ -14,6 +14,7 @@ from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
 
+import sys
 
 from gevent._util import Interface
 from gevent._util import Attribute
@@ -160,11 +161,13 @@ class ILoop(Interface):
            it will be removed in the future.
         """
 
+    if sys.platform != "win32":
+
         def child(pid, trace=0, ref=True):
             """
             Create a watcher that fires for events on the child with process ID *pid*.
 
-        This is platform specific.
+            This is platform specific and not available on Windows.
             """
 
     def stat(path, interval=0.0, ref=True, priority=None):

src/gevent/tests/test__hub.py

@@ -212,7 +212,7 @@ class TestPeriodicMonitoringThread(greentest.TestCase):
 
         # We must make sure we have switched greenlets at least once,
         # otherwise we can't detect a failure.
-        gevent.sleep(0.0001)
+        gevent.sleep(hub.loop.approx_timer_resolution)
         assert hub.exception_stream is stream
         try:
             time.sleep(0.3) # Thrice the default