patch 9.0.1324: "gj" and "gk" do not move correctly over a closed fold

Problem:    "gj" and "gk" do not move correctly over a closed fold.
Solution:   Use the same code as used for "j"/"k" to go to the next/previous
            line. (Luuk van Baal, closes #12007)
diff --git a/src/normal.c b/src/normal.c
index f5a85ac..1ab1599 100644
--- a/src/normal.c
+++ b/src/normal.c
@@ -2344,20 +2344,11 @@
 	    else
 	    {
 		// to previous line
-#ifdef FEAT_FOLDING
-		// Move to the start of a closed fold.  Don't do that when
-		// 'foldopen' contains "all": it will open in a moment.
-		if (!(fdo_flags & FDO_ALL))
-		    (void)hasFolding(curwin->w_cursor.lnum,
-						&curwin->w_cursor.lnum, NULL);
-#endif
-		if (curwin->w_cursor.lnum == 1)
+		if (!cursor_up_inner(curwin, 1))
 		{
 		    retval = FAIL;
 		    break;
 		}
-		--curwin->w_cursor.lnum;
-
 		linelen = linetabsize_str(ml_get_curline());
 		if (linelen > width1)
 		    curwin->w_curswant += (((linelen - width1 - 1) / width2)
@@ -2380,17 +2371,11 @@
 	    else
 	    {
 		// to next line
-#ifdef FEAT_FOLDING
-		// Move to the end of a closed fold.
-		(void)hasFolding(curwin->w_cursor.lnum, NULL,
-						      &curwin->w_cursor.lnum);
-#endif
-		if (curwin->w_cursor.lnum == curbuf->b_ml.ml_line_count)
+		if (!cursor_down_inner(curwin, 1))
 		{
 		    retval = FAIL;
 		    break;
 		}
-		curwin->w_cursor.lnum++;
 		curwin->w_curswant %= width2;
 		// Check if the cursor has moved below the number display
 		// when width1 < width2 (with cpoptions+=n). Subtract width2
diff --git a/src/testdir/test_fold.vim b/src/testdir/test_fold.vim
index a35ea1e..e0119c4 100644
--- a/src/testdir/test_fold.vim
+++ b/src/testdir/test_fold.vim
Binary files differ
diff --git a/src/version.c b/src/version.c
index e6ccb92..8be5a6e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1324,
+/**/
     1323,
 /**/
     1322,