fix(tabpage): check if ROWS_AVAIL changed for resize (#19620)

N/A patches for version.c:

vim-patch:9.0.0135: comment about tabpage line above the wrong code

Problem:    Comment about tabpage line above the wrong code.
Solution:   Move the comment. (closes vim/vim#10836)
0b0ccbbfb0

test/functional/editor/tabpage_spec.lua

@@ -1,4 +1,5 @@
 local helpers = require('test.functional.helpers')(after_each)
+local Screen = require('test.functional.ui.screen')
 
 local clear = helpers.clear
 local command = helpers.command
@@ -53,6 +54,46 @@ describe('tabpage', function()
     neq(999, eval('g:win_closed'))
   end)
 
+  it('switching tabpage after setting laststatus=3 #19591', function()
+    local screen = Screen.new(40, 8)
+    screen:set_default_attr_ids({
+      [0] = {bold = true, foreground = Screen.colors.Blue},
+      [1] = {bold = true, reverse = true},  -- StatusLine
+      [2] = {reverse = true},  -- StatusLineNC, TabLineFill
+      [3] = {bold = true}, -- TabLineSel
+      [4] = {background = Screen.colors.LightGrey, underline = true},  -- TabLine
+      [5] = {bold = true, foreground = Screen.colors.Magenta},
+    })
+    screen:attach()
+
+    command('tabnew')
+    command('tabprev')
+    command('set laststatus=3')
+    command('tabnext')
+    feed('<C-G>')
+    screen:expect([[
+      {4: [No Name] }{3: [No Name] }{2:                 }{4:X}|
+      ^                                        |
+      {0:~                                       }|
+      {0:~                                       }|
+      {0:~                                       }|
+      {0:~                                       }|
+      {1:[No Name]                               }|
+      "[No Name]" --No lines in buffer--      |
+    ]])
+    command('vnew')
+    screen:expect([[
+      {4: [No Name] }{3: }{5:2}{3: [No Name] }{2:               }{4:X}|
+      ^                    │                   |
+      {0:~                   }│{0:~                  }|
+      {0:~                   }│{0:~                  }|
+      {0:~                   }│{0:~                  }|
+      {0:~                   }│{0:~                  }|
+      {1:[No Name]                               }|
+      "[No Name]" --No lines in buffer--      |
+    ]])
+  end)
+
   it(":tabmove handles modifiers and addr", function()
     command('tabnew | tabnew | tabnew')
     eq(4, funcs.nvim_tabpage_get_number(0))