vim-patch:8.0.1411: reading invalid memory with CTRL-W :

Problem:    Reading invalid memory with CTRL-W :.
Solution:   Correct the command characters. (closes vim/vim#2469)
2efb323e87

src/nvim/ops.c

@@ -153,6 +153,10 @@ int get_op_type(int char1, int char2)
     if (opchars[i][0] == char1 && opchars[i][1] == char2) {
       break;
     }
+    if (i == (int)(sizeof(opchars) / sizeof(char [3]) - 1)) {
+      internal_error("get_op_type()");
+      break;
+    }
   }
   return i;
 }