patch 8.0.0358: invalid memory access in C-indent code

Problem:    Invalid memory access in C-indent code.
Solution:   Don't go over end of empty line. (Dominique Pelle, closes #1492)
diff --git a/src/testdir/test_options.vim b/src/testdir/test_options.vim
index 1ee1f8f..076d8b2 100644
--- a/src/testdir/test_options.vim
+++ b/src/testdir/test_options.vim
@@ -135,6 +135,13 @@
   call assert_fails("set " . a:name . "=/not.*there", "E474:")
 endfunc
 
+func Test_cinkeys()
+  " This used to cause invalid memory access
+  set cindent cinkeys=0
+  norm a
+  set cindent& cinkeys&
+endfunc
+
 func Test_dictionary()
   call Check_dir_option('dictionary')
 endfunc