don't emit an error message for every face that could not be added (due to complex elements)

Status Job ID Name Coverage
  Test
passed #4093
Linux
clang-c++11

00:21:24

passed #4095
Linux
clang-c++98

00:17:21

passed #4092
Linux
gcc-c++11

00:04:18

passed #4094
Linux
gcc-c++98

00:03:58

passed #4096
Apple
macos-c++11

00:16:30

passed #4097
Apple
macos-c++98

00:08:29