patch 8.0.0539: startup test fails on Mac

Problem:    Startup test fails on Mac.
Solution:   Use another term name, "unknown" is known. Avoid a 2 second delay.

src/main.c

@@ -1012,6 +1012,15 @@ common_init(mparm_T *paramp)
 #endif
 }
 
+/*
+ * Return TRUE when the --not-a-term argument was found.
+ */
+    int
+is_not_a_term()
+{
+    return params.not_a_term;
+}
+
 /*
  * Main loop: Execute Normal mode commands until exiting Vim.
  * Also used to handle commands in the command-line window, until the window

src/proto/main.pro

@@ -1,6 +1,7 @@
 /* main.c */
 int vim_main2(void);
 void common_init(mparm_T *paramp);
+int is_not_a_term(void);
 void main_loop(int cmdwin, int noexmode);
 void getout_preserve_modified(int exitval);
 void getout(int exitval);

src/term.c

@@ -1705,6 +1705,7 @@ set_termname(char_u *term)
 		{
 		    screen_start();	/* don't know where cursor is now */
 		    out_flush();
+		    if (!is_not_a_term())
 			ui_delay(2000L, TRUE);
 		}
 		set_string_option_direct((char_u *)"term", -1, term,

src/testdir/test_startup.vim

@@ -216,7 +216,7 @@ func Test_default_term()
   endif
 
   let save_term = $TERM
-  let $TERM = 'unknown'
+  let $TERM = 'unknownxxx'
   let out = system(GetVimCommand() . ' -c''set term'' -c cq')
   call assert_match("defaulting to 'ansi'", out)
   let $TERM = save_term

src/version.c

@@ -764,6 +764,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    539,
 /**/
     538,
 /**/