patch 8.0.1637: no test for term_dumpdiff() options argument

Problem:    No test for term_dumpdiff() options argument.
Solution:   Add a test.
diff --git a/src/testdir/test_terminal.vim b/src/testdir/test_terminal.vim
index 29e2d7b..f2fbaf4 100644
--- a/src/testdir/test_terminal.vim
+++ b/src/testdir/test_terminal.vim
@@ -995,3 +995,31 @@
   call assert_equal('           bbbbbbbbbbbbbbbbbb ', getline(26)[0:29])
   quit
 endfunc
+
+func Test_terminal_dumpdiff_options()
+  set laststatus=0
+  call assert_equal(1, winnr('$'))
+  let height = winheight(0)
+  call term_dumpdiff('dumps/Test_popup_command_01.dump', 'dumps/Test_popup_command_02.dump', {'vertical': 1, 'term_cols': 33})
+  call assert_equal(2, winnr('$'))
+  call assert_equal(height, winheight(winnr()))
+  call assert_equal(33, winwidth(winnr()))
+  call assert_equal('dump diff dumps/Test_popup_command_01.dump', bufname('%'))
+  quit
+
+  call assert_equal(1, winnr('$'))
+  let width = winwidth(0)
+  call term_dumpdiff('dumps/Test_popup_command_01.dump', 'dumps/Test_popup_command_02.dump', {'vertical': 0, 'term_rows': 13, 'term_name': 'something else'})
+  call assert_equal(2, winnr('$'))
+  call assert_equal(width, winwidth(winnr()))
+  call assert_equal(13, winheight(winnr()))
+  call assert_equal('something else', bufname('%'))
+  quit
+
+  call assert_equal(1, winnr('$'))
+  call term_dumpdiff('dumps/Test_popup_command_01.dump', 'dumps/Test_popup_command_02.dump', {'curwin': 1})
+  call assert_equal(1, winnr('$'))
+  bwipe
+
+  set laststatus&
+endfunc
diff --git a/src/version.c b/src/version.c
index 71a67ce..0249efb 100644
--- a/src/version.c
+++ b/src/version.c
@@ -767,6 +767,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1637,
+/**/
     1636,
 /**/
     1635,