patch 9.0.0756: no autocmd event for changing text in a terminal window

Problem:    No autocmd event for changing text in a terminal window.
Solution:   Add TextChangedT. (Shougo Matsushita, closes #11366)
diff --git a/src/testdir/test_terminal.vim b/src/testdir/test_terminal.vim
index 69faa3d..d0ffe3b 100644
--- a/src/testdir/test_terminal.vim
+++ b/src/testdir/test_terminal.vim
@@ -2321,5 +2321,54 @@
   bwipe!
 endfunc
 
+func Test_term_TextChangedT()
+  augroup TermTest
+    autocmd TextChangedT * ++once
+          \ execute expand('<abuf>') . 'buffer' |
+          \ let b:called = 1 |
+          \ split |
+          \ enew
+  augroup END
+
+  terminal
+
+  let term_buf = bufnr()
+
+  let b:called = 0
+
+  call term_sendkeys(term_buf, "aaabbc\r")
+  call TermWait(term_buf)
+
+  call assert_equal(1, getbufvar(term_buf, 'called'))
+
+  " Current buffer will be restored
+  call assert_equal(bufnr(), term_buf)
+
+  bwipe!
+  augroup TermTest
+    au!
+  augroup END
+endfunc
+
+func Test_term_TextChangedT_close()
+  augroup TermTest
+    autocmd TextChangedT * ++once split | enew | 1close!
+  augroup END
+
+  terminal
+
+  let term_buf = bufnr()
+
+  call term_sendkeys(term_buf, "aaabbc\r")
+  call TermWait(term_buf)
+
+  " Current buffer will be restored
+  call assert_equal(bufnr(), term_buf)
+
+  bwipe!
+  augroup TermTest
+    au!
+  augroup END
+endfunc
 
 " vim: shiftwidth=2 sts=2 expandtab