patch 7.4.1926

Problem:    Possible crash with many history items.
Solution:   Avoid the index going past the last item.

src/ex_getln.c

@@ -6448,7 +6448,7 @@ merge_history(int type)
 	else
 	    clear_hist_entry(&new_hist[i]);
     }
-    hisidx[type] = len - 1;
+    hisidx[type] = (i < len ? i : len) - 1;
 
     /* Free what is not kept. */
     for (i = 0; i < viminfo_hisidx[type]; i++)

src/version.c

@@ -753,6 +753,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1926,
 /**/
     1925,
 /**/