patch 8.1.1263: mouse clicks in WinBar not tested

Problem:    Mouse clicks in WinBar not tested.
Solution:   Add a test for clicking on the WinBar entries.
diff --git a/src/testdir/test_winbar.vim b/src/testdir/test_winbar.vim
index 1961607..fd44ac9 100644
--- a/src/testdir/test_winbar.vim
+++ b/src/testdir/test_winbar.vim
@@ -21,3 +21,47 @@
   aunmenu WinBar.Cont
   close
 endfunc
+
+func Test_click_in_winbar()
+  new
+  amenu 1.10 WinBar.Next :let g:did_next = 11<CR>
+  amenu 1.20 WinBar.Cont :let g:did_cont = 12<CR>
+  amenu 1.30 WinBar.Close :close<CR>
+  redraw
+
+  let save_mouse = &mouse
+  set mouse=a
+
+  " Columns of the button edges:
+  " _Next_  _Cont_  _Close_
+  " 2    7  10  15  18   24
+  let g:did_next = 0
+  let g:did_cont = 0
+  for col in [1, 8, 9, 16, 17, 25, 26]
+    call test_setmouse(1, 1)
+    call feedkeys("\<LeftMouse>", "xt")
+    call assert_equal(0, g:did_next, 'col ' .. col)
+    call assert_equal(0, g:did_cont, 'col ' .. col)
+  endfor
+
+  for col in range(2, 7)
+    let g:did_next = 0
+    call test_setmouse(1, col)
+    call feedkeys("\<LeftMouse>", "xt")
+    call assert_equal(11, g:did_next, 'col ' .. col)
+  endfor
+
+  for col in range(10, 15)
+    let g:did_cont = 0
+    call test_setmouse(1, col)
+    call feedkeys("\<LeftMouse>", "xt")
+    call assert_equal(12, g:did_cont, 'col ' .. col)
+  endfor
+
+  let wincount = winnr('$')
+  call test_setmouse(1, 20)
+  call feedkeys("\<LeftMouse>", "xt")
+  call assert_equal(wincount - 1, winnr('$'))
+
+  let &mouse = save_mouse
+endfunc
diff --git a/src/version.c b/src/version.c
index 07f3962..f5faef3 100644
--- a/src/version.c
+++ b/src/version.c
@@ -768,6 +768,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1263,
+/**/
     1262,
 /**/
     1261,