Add missing test files from 7.4.634 to the repository.

src/testdir/test_marks.in

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+Tests for marks.
+
+STARTTEST
+:so small.vim
+:" test that a deleted mark is restored after delete-undo-redo-undo
+:/^\t/+1
+:set nocp viminfo+=nviminfo
+madduu
+:let a = string(getpos("'a"))
+:$put ='Mark after delete-undo-redo-undo: '.a
+:/^\t/,$wq! test.out
+ENDTEST
+
+	textline A
+	textline B
+	textline C
+
+Results:

src/testdir/test_marks.ok

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+	textline A
+	textline B
+	textline C
+
+Results:
+Mark after delete-undo-redo-undo: [0, 15, 2, 0]