Remove workaround affecting --list-tests --gtest_filter=X. One of the multiple workarounds added in https://crrev.com/c/3062240. It makes `--list-tests --gtest_filter=X` behave as if it was just `--list-tests`. Not sure why this was necessary, bots appear to work without it?.. Could be something that changed since that CL? Bug: angleproject:7508 Change-Id: I9988add40ddf3168e00cea2739e5a9209f633161 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3821374 Reviewed-by: Yuxin Hu <yuxinhu@google.com>