Merge changes I6541bb13,I486055bb,Id6ac1c54,I16cf7d44

* changes:
  adb: make fdevent_test, socket_test compile on Windows.
  adb: add fd exhaustion test, fix errno reporting in sysdeps_win32.
  adb: move win32 fd base to 2048, fix fd allocation.
  adb: don't emulate fdevent or socketpair on Windows.