patch 8.2.1414: popupwindow missing last couple of lines

Problem:    Popupwindow missing last couple of lines when cursor is in the
            first line.
Solution:   Compute the max height also when top aligned. (closes #6664)
diff --git a/src/testdir/dumps/Test_popupwin_nospace.dump b/src/testdir/dumps/Test_popupwin_nospace.dump
index 9eaacf0..de8521c 100644
--- a/src/testdir/dumps/Test_popupwin_nospace.dump
+++ b/src/testdir/dumps/Test_popupwin_nospace.dump
@@ -3,10 +3,10 @@
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 |-|╚+0#0000001#ffd7ff255|═@2|╝|-+0#0000000#ffffff0@1|╚+0#0000001#ffd7ff255|═@2|╝|-+0#0000000#ffffff0@8|║+0#0000001#ffd7ff255|c@2|║|-+0#0000000#ffffff0@15|║+0#0000001#ffd7ff255|t|e@1|║|-+0#0000000#ffffff0@11| @14
 |-|@|-@5|#|-@5|%|-@5|║+0#0000001#ffd7ff255|d@2|║|-+0#0000000#ffffff0@15|║+0#0000001#ffd7ff255|f|o|u|║|-+0#0000000#ffffff0@1>*|-@8| @14
-|-@14|╔+0#0000001#ffd7ff255|═@2|╗|-+0#0000000#ffffff0@1|║+0#0000001#ffd7ff255|e@2|║|-+0#0000000#ffffff0@15|║+0#0000001#ffd7ff255|f|i|v|║|-+0#0000000#ffffff0@1|╔+0#0000001#ffd7ff255|═@2|╗|-+0#0000000#ffffff0@4| @14
-|-@14|║+0#0000001#ffd7ff255|o|n|e|║|-+0#0000000#ffffff0@1|╚+0#0000001#ffd7ff255|═@2|╝|-+0#0000000#ffffff0@15|╚+0#0000001#ffd7ff255|═@2|╝|-+0#0000000#ffffff0@1|║+0#0000001#ffd7ff255|a@2|║|-+0#0000000#ffffff0@4| @14
-|-@14|║+0#0000001#ffd7ff255|t|w|o|║|-+0#0000000#ffffff0@1|*|-@5|@|-@5|#|-@5|%|-@5|║+0#0000001#ffd7ff255|b@2|║|-+0#0000000#ffffff0@4| @14
-|-@14|║+0#0000001#ffd7ff255|t|e@1|║|-+0#0000000#ffffff0@8|╔+0#0000001#ffd7ff255|═@2|╗|-+0#0000000#ffffff0@1|╔+0#0000001#ffd7ff255|═@2|╗|-+0#0000000#ffffff0@8|║+0#0000001#ffd7ff255|c@2|║|-+0#0000000#ffffff0@4| @14
-|-@14|╚+0#0000001#ffd7ff255|═@2|╝|-+0#0000000#ffffff0@8|║+0#0000001#ffd7ff255|o|n|e|║|-+0#0000000#ffffff0@1|║+0#0000001#ffd7ff255|o|n|e|║|-+0#0000000#ffffff0@8|║+0#0000001#ffd7ff255|d@2|║|-+0#0000000#ffffff0@4| @14
-|-@28|║+0#0000001#ffd7ff255|t|w|o|║|-+0#0000000#ffffff0@1|║+0#0000001#ffd7ff255|t|w|o|║|-+0#0000000#ffffff0@8|║+0#0000001#ffd7ff255|e@2|║|-+0#0000000#ffffff0@4| @14
-@29|╚+0#0000001#ffd7ff255|═@2|╝| +0#0000000#ffffff0@1|║+0#0000001#ffd7ff255|t|e@1|║| +0#0000000#ffffff0@8|║+0#0000001#ffd7ff255|f@2|║| +0#0000000#ffffff0@1|5|,|5|1| @9|T|o|p| 
+|-@14|╔+0#0000001#ffd7ff255|═@2|╗|-+0#0000000#ffffff0@1|║+0#0000001#ffd7ff255|e@2|║|-+0#0000000#ffffff0@15|║+0#0000001#ffd7ff255|f|i|v|║|-+0#0000000#ffffff0@1|╔+0#0000001#ffd7ff255|═@3|╗|-+0#0000000#ffffff0@3| @14
+|-@14|║+0#0000001#ffd7ff255|o|n|e|║|-+0#0000000#ffffff0@1|╚+0#0000001#ffd7ff255|═@2|╝|-+0#0000000#ffffff0@15|╚+0#0000001#ffd7ff255|═@2|╝|-+0#0000000#ffffff0@1|║+0#0000001#ffd7ff255|a@2| +0#0000000#0000001|║+0#0000001#ffd7ff255|-+0#0000000#ffffff0@3| @14
+|-@14|║+0#0000001#ffd7ff255|t|w|o|║|-+0#0000000#ffffff0@1|*|-@5|@|-@5|#|-@5|%|-@5|║+0#0000001#ffd7ff255|b@2| +0#0000000#0000001|║+0#0000001#ffd7ff255|-+0#0000000#ffffff0@3| @14
+|-@14|║+0#0000001#ffd7ff255|t|e@1|║|-+0#0000000#ffffff0@8|╔+0#0000001#ffd7ff255|═@2|╗|-+0#0000000#ffffff0@1|╔+0#0000001#ffd7ff255|═@3|╗|-+0#0000000#ffffff0@7|║+0#0000001#ffd7ff255|c@2| +0#0000000#0000001|║+0#0000001#ffd7ff255|-+0#0000000#ffffff0@3| @14
+|-@14|╚+0#0000001#ffd7ff255|═@2|╝|-+0#0000000#ffffff0@8|║+0#0000001#ffd7ff255|o|n|e|║|-+0#0000000#ffffff0@1|║+0#0000001#ffd7ff255|o|n|e| +0#0000000#0000001|║+0#0000001#ffd7ff255|-+0#0000000#ffffff0@7|║+0#0000001#ffd7ff255|d@2| +0#0000000#0000001|║+0#0000001#ffd7ff255|-+0#0000000#ffffff0@3| @14
+|-@28|║+0#0000001#ffd7ff255|t|w|o|║|-+0#0000000#ffffff0@1|║+0#0000001#ffd7ff255|t|w|o| +0#0000000#a8a8a8255|║+0#0000001#ffd7ff255|-+0#0000000#ffffff0@7|║+0#0000001#ffd7ff255|e@2| +0#0000000#a8a8a8255|║+0#0000001#ffd7ff255|-+0#0000000#ffffff0@3| @14
+@29|╚+0#0000001#ffd7ff255|═@2|╝| +0#0000000#ffffff0@1|╚+0#0000001#ffd7ff255|═@3|╝| +0#0000000#ffffff0@7|╚+0#0000001#ffd7ff255|═@3|╝| +0#0000000#ffffff0|5|,|5|1| @9|T|o|p|