vim-patch:9.0.0071: command overlaps with printed text in scrollback (#19505)

Problem:    Command overlaps with printed text in scrollback.
Solution:   Clear until end-of-line and use correct message chunk.
            (closes vim/vim#10765, closes vim/vim#10764)
ecdc82e74e

N/A patches for version.c:

vim-patch:9.0.0070: using utfc_ptr2char_len() when length is negative

Problem:    Using utfc_ptr2char_len() when length is negative.
Solution:   Check value of length. (closes vim/vim#10760)
4dc513a22c

test/functional/terminal/tui_spec.lua

@@ -144,10 +144,9 @@ describe('TUI', function()
       {3:-- TERMINAL --}                                    |
     ]]}
 
-    -- TODO(bfredl): messes up the output (just like vim does).
     feed_data('g')
     screen:expect{grid=[[
-                    )                                   |
+      :call ManyErr()                                   |
       {8:Error detected while processing function ManyErr:} |
       {11:line    2:}                                        |
       {10:-- More --}{1: }                                       |
@@ -156,7 +155,7 @@ describe('TUI', function()
 
     screen:try_resize(50,10)
     screen:expect{grid=[[
-                    )                                   |
+      :call ManyErr()                                   |
       {8:Error detected while processing function ManyErr:} |
       {11:line    2:}                                        |
       {8:FAIL 0}                                            |