vim-patch:8.1.0822: peeking and flushing output slows down execution

Problem:    Peeking and flushing output slows down execution.
Solution:   Do not update the mode message when global_busy is set.  Do not
            flush when only peeking for a character. (Ken Takata)
cb574f4154

test/functional/eval/null_spec.lua

@@ -121,7 +121,7 @@ describe('NULL', function()
     null_test('does not make Neovim crash when v:oldfiles gets assigned to that', ':let v:oldfiles = L|oldfiles', 0)
     null_expr_test('does not make complete() crash or error out',
                    'execute(":normal i\\<C-r>=complete(1, L)[-1]\\n")',
-                   '', '\n', function()
+                   0, '', function()
       eq({''}, curbufmeths.get_lines(0, -1, false))
     end)
     null_expr_test('is accepted by setmatches()', 'setmatches(L)', 0, 0)

test/functional/eval/timer_spec.lua

@@ -130,12 +130,12 @@ describe('timers', function()
     nvim_async("command", "call timer_start("..load_adjust(100)..", 'AddItem', {'repeat': -1})")
 
     screen:expect([[
-      ITEM 1                                  |
+      ^ITEM 1                                  |
       ITEM 2                                  |
       {1:~                                       }|
       {1:~                                       }|
       {1:~                                       }|
-      ^                                        |
+                                              |
     ]])
     nvim_async("command", "let g:cont = 1")
 

test/functional/terminal/tui_spec.lua

@@ -391,7 +391,7 @@ describe('TUI', function()
       {1:x}                                                 |
       {4:~                                                 }|
       {5:[No Name] [+]                   3,1            All}|
-                                                        |
+      :set ruler                                        |
       {3:-- TERMINAL --}                                    |
     ]]
     local expected_attr = {

test/functional/ui/screen.lua

@@ -807,7 +807,9 @@ function Screen:_handle_mouse_off()
 end
 
 function Screen:_handle_mode_change(mode, idx)
-  assert(mode == self._mode_info[idx+1].name)
+  if self._mode_info ~= nil then
+    assert(mode == self._mode_info[idx+1].name)
+  end
   self.mode = mode
 end