patch 9.1.0710: popup window may hide part of Command line

Problem:  when a popup window covers the command line,
          the command line is not completely cleared on popup_hide()
          (yu3s)
Solution: Check if the popup window covers the command line and if it
          does, set the clear_cmdline flag.

fixes: #15608
closes: #15610

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/dumps/Test_echowindow_9.dump b/src/testdir/dumps/Test_echowindow_9.dump
index 2efdef0..8c48d62 100644
--- a/src/testdir/dumps/Test_echowindow_9.dump
+++ b/src/testdir/dumps/Test_echowindow_9.dump
@@ -4,5 +4,5 @@
 |~| @73
 |~| @73
 |~| @73
-|:+0#0000000&|c|a|l@1| |H|i|d|e|W|i|n|(|)| @59
+| +0#0000000&@74
 @57|0|,|0|-|1| @8|A|l@1| 
diff --git a/src/testdir/dumps/Test_popupwin_hide_clear_cmdline_01.dump b/src/testdir/dumps/Test_popupwin_hide_clear_cmdline_01.dump
new file mode 100644
index 0000000..25a79ea
--- /dev/null
+++ b/src/testdir/dumps/Test_popupwin_hide_clear_cmdline_01.dump
@@ -0,0 +1,10 @@
+>f+0&#ffffff0|o@1|b|a|r| |o|n|e| |t|w|o| |t|h|r|e@1| @54
+|f|o@1|b|a|r| |o|n|e| |t|w|o| |t|h|r|e@1| @54
+|f|o@1|b|a|r| |o|n|e| |t|w|o| |t|h|r|e@1| @54
+|f|o@1|b|a|r| |o|n|e| |t|w|o| |t|h|r|e@1| @54
+|f|o@1|b|a|r| |o|n|e| |t|w|o| |t|h|r|e@1| @54
+|f|o@1|b|a|r| |o|n|e| |t|w|o| |t|h|r|e@1| @54
+|f|o@1|b|a|r| |o|n|e| |t|w|o| |t|h|r|e@1| @54
+|f|o@1|b|a|r| |o|n|e| |t|w|o| |t|h|r|e@1| @54
+|f|o@1|b|a|r| |o|n|e| |t|w|o| |t|h|r|e@1| @54
+@57|1|,|1| @10|T|o|p|