On 'win32-pollset-wakeup-no-file-socket-emulation' branch: Merge changes from
trunk.

git-svn-id: https://svn.apache.org/repos/asf/apr/apr/branches/win32-pollset-wakeup-no-file-socket-emulation@1897894 13f79535-47bb-0310-9956-ffa450edef68