chromeos-chrome started failing to build on veyron_minnie-tot-chrome-pfq-informational this morning (Nov 27).

Last passing: http://cros-goldeneye/chromeos/healthmonitoring/buildDetails?buildbucketId=8928713536981885584
First failed: http://cros-goldeneye/chromeos/healthmonitoring/buildDetails?buildbucketId=8928691162541012784

Here's the failure:

chromeos-chrome-72.0.3624.0_alpha-r1: FAILED: obj/media/gpu/gpu/generic_v4l2_device.o 
chromeos-chrome-72.0.3624.0_alpha-r1: /home/chrome-bot/goma/gomacc armv7a-cros-linux-gnueabihf-clang++ -B/usr/x86_64-pc-linux-gnu/armv7a-cros-linux-gnueabihf/binutils-bin/2.27.0-gold -MMD -MF obj/media/gpu/gpu/generic_v4l2_device.o.d -DMEDIA_GPU_IMPLEMENTATION -DV8_DEPRECATION_WARNINGS -DUSE_UDEV -DUSE_AURA=1 -DUSE_NSS_CERTS=1 -DUSE_OZONE=1 -DFULL_SAFE_BROWSING -DSAFE_BROWSING_CSD -DSAFE_BROWSING_DB_LOCAL -DOFFICIAL_BUILD -DGOOGLE_CHROME_BUILD -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -DNO_UNWIND_TABLES -D_GNU_SOURCE -DCR_CLANG_REVISION=\"346388-5\" -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D_FORTIFY_SOURCE=2 -DCR_SYSROOT_HASH=ef5c4f84bcafb7a3796d36bb1db7826317dde51c -DOS_CHROMEOS -DNDEBUG -DNVALGRIND -DDYNAMIC_ANNOTATIONS_ENABLED=0 -DWEBP_EXTERN=extern -DUSE_EGL -DVK_NO_PROTOTYPES -DU_USING_ICU_NAMESPACE=0 -DU_ENABLE_DYLOAD=0 -DUSE_CHROMIUM_ICU=1 -DU_STATIC_IMPLEMENTATION -DICU_UTIL_DATA_IMPL=ICU_UTIL_DATA_FILE -DUCHAR_TYPE=uint16_t -DGOOGLE_PROTOBUF_NO_RTTI -DGOOGLE_PROTOBUF_NO_STATIC_INITIALIZER -DHAVE_PTHREAD -DSK_HAS_PNG_LIBRARY -DSK_HAS_WEBP_LIBRARY -DSK_HAS_JPEG_LIBRARY -DSK_VULKAN_HEADER=\"../../skia/config/SkVulkanConfig.h\" -DSK_VULKAN=1 -DSK_SUPPORT_GPU=1 -DSK_GPU_WORKAROUNDS_HEADER=\"gpu/config/gpu_driver_bug_workaround_autogen.h\" -DVK_NO_PROTOTYPES -DLEVELDB_PLATFORM_CHROMIUM=1 -DLEVELDB_PLATFORM_CHROMIUM=1 -I../../../../../../../home/chrome-bot/chrome_root/src -Igen -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/libwebp/src -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/libyuv/include -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/khronos -I../../../../../../../home/chrome-bot/chrome_root/src/gpu -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/vulkan/include -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/ced/src -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/icu/source/common -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/icu/source/i18n -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/protobuf/src -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/libwebm/source -I../../../../../../../home/chrome-bot/chrome_root/src/skia/config -I../../../../../../../home/chrome-bot/chrome_root/src/skia/ext -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/include/c -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/include/config -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/include/core -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/include/docs -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/include/effects -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/include/encode -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/include/gpu -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/include/pathops -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/include/ports -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/include/utils -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/vulkan/include -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/third_party/vulkanmemoryallocator -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/include/codec -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/src/gpu -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/src/sksl -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/skia/modules/skottie/include -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/vulkan/include -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/protobuf/src -Igen/protoc_out -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/leveldatabase -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/leveldatabase/src -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/leveldatabase/src/include -I../../../../../../../home/chrome-bot/chrome_root/src/third_party/mesa_headers -fno-strict-aliasing -fno-unwind-tables -fno-asynchronous-unwind-tables -fPIC -pthread -fcolor-diagnostics -fmerge-all-constants -Xclang -mllvm -Xclang -instcombine-lower-dbg-declare=0 -Xclang -fdebug-compilation-dir -Xclang . -no-canonical-prefixes -flto=thin -fwhole-program-vtables --target=arm-linux-gnueabihf -march=armv7-a -mfloat-abi=hard -mtune=generic-armv7-a -mfpu=neon -mthumb -Wall -Wextra -Wimplicit-fallthrough -Wthread-safety -Wno-missing-field-initializers -Wno-unused-parameter -Wno-c++11-narrowing -Wno-unneeded-internal-declaration -Wno-undefined-var-template -Wno-null-pointer-arithmetic -Wno-ignored-pragma-optimize -O2 -fno-ident -fdata-sections -ffunction-sections -fno-omit-frame-pointer -g2 -gsplit-dwarf -ggnu-pubnames -fsanitize=cfi-vcall -fsanitize-blacklist=../../../../../../../home/chrome-bot/chrome_root/src/tools/cfi/blacklist.txt -fsanitize=cfi-derived-cast -fsanitize=cfi-unrelated-cast -fvisibility=hidden -Wheader-hygiene -Wstring-conversion -Wtautological-overlap-compare -std=c++14 -fno-exceptions -fno-rtti --sysroot=../../../../../../../build/veyron_minnie -fvisibility-inlines-hidden -pipe -mcpu=cortex-a12 -mtune=cortex-a12 -mfpu=neon -mfloat-abi=hard -fno-split-dwarf-inlining -D__google_stl_debug_vector=1 -Wno-unknown-warning-option -stdlib=libc++  -c ../../../../../../../home/chrome-bot/chrome_root/src/media/gpu/v4l2/generic_v4l2_device.cc -o obj/media/gpu/gpu/generic_v4l2_device.o
chromeos-chrome-72.0.3624.0_alpha-r1: ../../../../../../../home/chrome-bot/chrome_root/src/media/gpu/v4l2/generic_v4l2_device.cc:39:10: fatal error: 'media/gpu/v4l2/v4l2_stubs.h' file not found
chromeos-chrome-72.0.3624.0_alpha-r1: #include "media/gpu/v4l2/v4l2_stubs.h"
chromeos-chrome-72.0.3624.0_alpha-r1:          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
chromeos-chrome-72.0.3624.0_alpha-r1: 1 error generated.

As best as I can tell, that code gets turned on by the "v4lplugin" Chrome OS USE flag. I can't find any recent changes here, either in Chrome, the chromeos-chrome ebuild, or overlay-veyron's package.use file. It looks like that file has contained "chromeos-base/chromeos-chrome v4lplugin" since 2014.

Presumably this was triggered by an OS change, based on the timing.