patch 8.1.2373: cannot build with +popupwin but without +quickfix

Problem:    Cannot build with +popupwin but without +quickfix. (John Marriott)
Solution:   Adjust #ifdefs.
diff --git a/src/testdir/test_window_cmd.vim b/src/testdir/test_window_cmd.vim
index d958c36..d543ef7 100644
--- a/src/testdir/test_window_cmd.vim
+++ b/src/testdir/test_window_cmd.vim
@@ -175,6 +175,8 @@
 endfunc
 
 func Test_window_preview()
+  CheckFeature quickfix
+
   " Open a preview window
   pedit Xa
   call assert_equal(2, winnr('$'))
@@ -193,6 +195,8 @@
 endfunc
 
 func Test_window_preview_from_help()
+  CheckFeature quickfix
+
   filetype on
   call writefile(['/* some C code */'], 'Xpreview.c')
   help
@@ -438,6 +442,8 @@
 endfunc
 
 func Test_win_screenpos()
+  CheckFeature quickfix
+
   call assert_equal(1, winnr('$'))
   split
   vsplit
@@ -451,6 +457,8 @@
 endfunc
 
 func Test_window_jump_tag()
+  CheckFeature quickfix
+
   help
   /iccf
   call assert_match('^|iccf|',  getline('.'))
@@ -887,6 +895,8 @@
 endfunc
 
 func Test_win_splitmove()
+  CheckFeature quickfix
+
   edit a
   leftabove split b
   leftabove vsplit c