patch 7.4.2151
Problem:    Quickfix test fails on MS-Windows.
Solution:   Close the help window. (Christian Brabandt)
diff --git a/src/testdir/test_quickfix.vim b/src/testdir/test_quickfix.vim
index e79315b..9f0b510 100644
--- a/src/testdir/test_quickfix.vim
+++ b/src/testdir/test_quickfix.vim
@@ -407,6 +407,7 @@
 
 function Test_helpgrep()
   call s:test_xhelpgrep('c')
+  helpclose
   call s:test_xhelpgrep('l')
 endfunc