https://cros-goldeneye.corp.google.com/chromeos/healthmonitoring/buildDetails?buildbucketId=8948345473588148432

chromeos-chrome-68.0.3406.0_alpha-r1:  * GN_ARGS = is_debug=false  use_v4l2_codec=true use_v4lplugin=false use_vaapi=true use_ozone=true use_evdev_gestures=true use_xkbcommon=true linux_use_bundled_binutils=false use_debug_fission=false enable_remoting=true enable_nacl=true icu_use_data_file=true use_cras=true use_system_harfbuzz=true use_system_freetype=true use_system_libsync=true use_cups=true use_jumbo_build=false use_bundled_fontconfig=false is_asan=false is_clang=true cros_host_is_clang=true clang_use_chrome_plugins=false use_thin_lto=false use_lld=false is_cfi=false use_cfi_cast=false ozone_auto_platforms=false ozone_platform_gbm=true use_system_minigbm=true use_system_libdrm=true treat_warnings_as_errors=false use_goma=true use_debug_fission=true symbol_level=2 target_sysroot="/build/amd64-generic" system_libdir="lib64" pkg_config="/build/amd64-generic/build/bin/pkg-config" target_os="chromeos" host_pkg_config="x86_64-pc-linux-gnu-pkg-config" ozone_platform="gbm" target_cpu="x64" goma_dir="/home/chrome-bot/goma" cros_target_ar="llvm-ar" cros_target_cc="x86_64-cros-linux-gnu-clang -B/usr/x86_64-pc-linux-gnu/x86_64-cros-linux-gnu/binutils-bin/2.27.0-gold" cros_target_cxx="x86_64-cros-linux-gnu-clang++ -B/usr/x86_64-pc-linux-gnu/x86_64-cros-linux-gnu/binutils-bin/2.27.0-gold" host_toolchain="//build/toolchain/cros:host" custom_toolchain="//build/toolchain/cros:target" v8_snapshot_toolchain="//build/toolchain/cros:v8_snapshot" cros_target_ld="x86_64-cros-linux-gnu-clang++ -B/usr/x86_64-pc-linux-gnu/x86_64-cros-linux-gnu/binutils-bin/2.27.0-gold" cros_target_extra_cflags="-pipe -pipe -march=x86-64 -msse3 -fno-split-dwarf-inlining -fdebug-info-for-profiling -Wno-unknown-warning-option " cros_target_extra_cppflags="" cros_target_extra_cxxflags="-pipe -pipe -pipe -march=x86-64 -msse3 -fno-split-dwarf-inlining -fdebug-info-for-profiling -D__google_stl_debug_vector=1 -Wno-unknown-warning-option -stdlib=libc++ " cros_target_extra_ldflags="-Wl,-O1 -Wl,-O2 -Wl,--as-needed -stdlib=libc++ " cros_host_cc="x86_64-pc-linux-gnu-clang -B/usr/bin" cros_host_cxx="x86_64-pc-linux-gnu-clang++ -B/usr/bin" cros_host_ar="llvm-ar" cros_host_ld="x86_64-pc-linux-gnu-clang++" cros_host_extra_cflags=" -Wno-unknown-warning-option" cros_host_extra_cxxflags=" -Wno-unknown-warning-option" cros_host_extra_cppflags="" cros_host_extra_ldflags="" cros_v8_snapshot_cc="x86_64-pc-linux-gnu-clang -B/usr/bin" cros_v8_snapshot_cxx="x86_64-pc-linux-gnu-clang++ -B/usr/bin" cros_v8_snapshot_ar="llvm-ar" cros_v8_snapshot_ld="x86_64-pc-linux-gnu-clang++" cros_v8_snapshot_extra_cflags=" -Wno-unknown-warning-option" cros_v8_snapshot_extra_cxxflags=" -Wno-unknown-warning-option" cros_v8_snapshot_extra_cppflags="" cros_v8_snapshot_extra_ldflags=""
chromeos-chrome-68.0.3406.0_alpha-r1: ERROR at //components/nacl/features.gni:13:7: Undefined identifier
chromeos-chrome-68.0.3406.0_alpha-r1:       checkout_nacl && !is_ios && !is_android && !is_fuchsia &&
chromeos-chrome-68.0.3406.0_alpha-r1:       ^------------
chromeos-chrome-68.0.3406.0_alpha-r1: See //BUILD.gn:15:1: whence it was imported.
chromeos-chrome-68.0.3406.0_alpha-r1: import("//components/nacl/features.gni")
chromeos-chrome-68.0.3406.0_alpha-r1: ^--------------------------------------
chromeos-chrome-68.0.3406.0_alpha-r1:  * ERROR: chromeos-base/chromeos-chrome-68.0.3406.0_alpha-r1::chromiumos failed (configure phase):
chromeos-chrome-68.0.3406.0_alpha-r1:  *   (no error message)
chromeos-chrome-68.0.3406.0_alpha-r1:  * 
chromeos-chrome-68.0.3406.0_alpha-r1:  * Call stack:
chromeos-chrome-68.0.3406.0_alpha-r1:  *     ebuild.sh, line 133:  Called src_configure
chromeos-chrome-68.0.3406.0_alpha-r1:  *   environment, line 4308:  Called die
chromeos-chrome-68.0.3406.0_alpha-r1:  * The specific snippet of code:
chromeos-chrome-68.0.3406.0_alpha-r1:  *       ${EGN} gen "${CHROME_ROOT}/src/${BUILD_OUT_SYM}/${BUILDTYPE}" --args="${GN_ARGS}" --root="${CHROME_ROOT}/src" || die;