patch 8.0.0361: GUI initialisation is not sufficiently tested

Problem:    GUI initialisation is not sufficiently tested.
Solution:   Add the gui_init test. (Kazuki Kuriyama)
diff --git a/Filelist b/Filelist
index a3c8f54..316a403 100644
--- a/Filelist
+++ b/Filelist
@@ -105,7 +105,10 @@
 		src/testdir/sautest/autoload/*.vim \
 		src/testdir/runtest.vim \
 		src/testdir/shared.vim \
+		src/testdir/view_util.vim \
 		src/testdir/setup.vim \
+		src/testdir/gui_init.vim \
+		src/testdir/setup_gui.vim \
 		src/testdir/test[0-9]*.ok \
 		src/testdir/test[0-9]*a.ok \
 		src/testdir/test_[a-z]*.ok \