patch 9.0.1648: result of syntax tests is hard to see

Problem:    Result of syntax tests is hard to see.
Solution:   List the failed tests.
diff --git a/runtime/syntax/Makefile b/runtime/syntax/Makefile
index 08bc824..a52c7d6 100644
--- a/runtime/syntax/Makefile
+++ b/runtime/syntax/Makefile
@@ -26,7 +26,7 @@
 	@echo "../$(VIMPROG)" > testdir/vimcmd
 	@echo "$(RUN_VIMTEST)" >> testdir/vimcmd
 	VIMRUNTIME=$(VIMRUNTIME) $(VIMPROG) --clean --not-a-term $(DEBUGLOG) -u testdir/runtest.vim
-	@tail -n 5 testdir/messages
+	@tail -n 6 testdir/messages
 
 
 clean testclean:
diff --git a/runtime/syntax/testdir/runtest.vim b/runtime/syntax/testdir/runtest.vim
index 21e1ae3..9e2739f 100644
--- a/runtime/syntax/testdir/runtest.vim
+++ b/runtime/syntax/testdir/runtest.vim
@@ -40,7 +40,8 @@
 exe 'split ' .. s:messagesFname
 call append(line('$'), repeat('=-', 70))
 call append(line('$'), '')
-call append(line('$'), 'Test run on ' .. strftime("%Y %b %d %H:%M:%S"))
+let s:test_run_message = 'Test run on ' .. strftime("%Y %b %d %H:%M:%S")
+call append(line('$'), s:test_run_message)
 wq
 
 if syntaxDir !~ '[/\\]runtime[/\\]syntax\>'
@@ -86,7 +87,7 @@
 
 
 let ok_count = 0
-let failed_count = 0
+let failed_tests = []
 let skipped_count = 0
 let MAX_FAILED_COUNT = 5
 for fname in glob('input/*.*', 1, 1)
@@ -162,20 +163,21 @@
 
       call delete('done/' .. root)
 
-      let failed_count += 1
-      if failed_count > MAX_FAILED_COUNT
+      call failed_tests->extend(root)
+      if len(failed_tests) > MAX_FAILED_COUNT
 	call Message('')
 	call Message('Too many errors, aborting')
       endif
     endif
   else
+    call Message("Test " .. root .. " skipped")
     let skipped_count += 1
   endif
 
   " Append messages to the file "testdir/messages"
   call AppendMessages('Input file ' .. fname .. ':')
 
-  if failed_count > MAX_FAILED_COUNT
+  if len(failed_tests) > MAX_FAILED_COUNT
     break
   endif
 endfor
@@ -183,12 +185,13 @@
 " Matching "if 1" at the start.
 endif
 
+call Message(s:test_run_message)
 call Message('OK: ' .. ok_count)
-call Message('FAILED: ' .. failed_count)
+call Message('FAILED: ' .. len(failed_tests) .. ': ' .. string(failed_tests))
 call Message('skipped: ' .. skipped_count)
 call AppendMessages('== SUMMARY ==')
 
-if failed_count > 0
+if len(failed_tests) > 0
   " have make report an error
   cquit
 endif
diff --git a/src/version.c b/src/version.c
index b027efd..191bf50 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1648,
+/**/
     1647,
 /**/
     1646,