This appears to be flaky behavior, as the subsequent run passed, but I've seen this on a few -release builders today.

https://cros-goldeneye.corp.google.com/chromeos/healthmonitoring/buildDetails?buildbucketId=8939251854679755312

These messages look relevant (I wonder why has_gomacc_path is ignored):
21:12:13: WARNING: No args.gn file: /b/swarming/w/ir/cache/cbuild/repository/.cache/distfiles/target-master/chrome-src-internal/src/out_daisy/Release/args.gn
21:12:13: WARNING: To update gn args run:
21:12:13: WARNING: gn gen out_$SDK_BOARD/Release --args="$GN_ARGS"
WARNING at the command-line "--args":41:19: Build argument has no effect.
has_gomacc_path = true
                  ^---
The variable "has_gomacc_path" was set as a build argument
but never appeared in a declare_args() block in any buildfile.

And the corresponding later failure message:
FAILED: obj/components/safe_browsing/web_ui/constants/constants.o 
/home/chrome-bot/goma/gomacc armv7a-cros-linux-gnueabi-clang++ -B../../../../../../../../../../tmp/t/cbuildbot-tmpzBwfd2/chrome-sdk-cacheEiHaO6/cache/chrome-sdk/tarballs/daisy+__b__swarming__w__ir__cache__cbuild__repository__buildbot_archive__daisy-release__R70-10933.0.0+target_toolchain/usr/x86_64-pc-linux-gnu/armv7a-cros-linux-gnueabi/binutils-bin/2.27.0-gold -Wno-unknown-warning-option -MMD -MF obj/components/safe_browsing/web_ui/constants/constants.o.d -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 -DCR_CLANG_REVISION=\"337439-1\" -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D_FORTIFY_SOURCE=2 -DCR_SYSROOT_HASH=b2165ab47ab9c4cc780db53ace1b08607d68ae31 -DOS_CHROMEOS -DNDEBUG -DNVALGRIND -DDYNAMIC_ANNOTATIONS_ENABLED=0 -I../.. -Igen -fno-strict-aliasing -fno-unwind-tables -fno-asynchronous-unwind-tables -fPIC -B../../third_party/binutils/Linux_x64/Release/bin -pthread -fcolor-diagnostics -fmerge-all-constants -Xclang -fdebug-compilation-dir -Xclang . -no-canonical-prefixes --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-covered-switch-default -Wno-unneeded-internal-declaration -Wno-undefined-var-template -Wno-nonportable-include-path -Wno-user-defined-warnings -Wno-unused-lambda-capture -Wno-null-pointer-arithmetic -Wno-enum-compare-switch -Wno-ignored-pragma-optimize -O2 -fno-ident -fdata-sections -ffunction-sections -fno-omit-frame-pointer -g2 -gsplit-dwarf -ggnu-pubnames -fvisibility=hidden -Wheader-hygiene -Wstring-conversion -Wtautological-overlap-compare -std=gnu++14 -fno-exceptions -fno-rtti --sysroot=../../../../../../../../../../tmp/t/cbuildbot-tmpzBwfd2/chrome-sdk-cacheEiHaO6/cache/chrome-sdk/tarballs/daisy+__b__swarming__w__ir__cache__cbuild__repository__buildbot_archive__daisy-release__R70-10933.0.0+sysroot_chromeos-base_chromeos-chrome.tar.xz -fvisibility-inlines-hidden -pipe -march=armv7-a -mtune=cortex-a15 -mfpu=neon -mfloat-abi=hard -fno-split-dwarf-inlining -D__google_stl_debug_vector=1 -Wno-unknown-warning-option -stdlib=libc++ -Wno-inline-asm -c ../../components/safe_browsing/web_ui/constants.cc -o obj/components/safe_browsing/web_ui/constants/constants.o
/bin/sh: 1: /home/chrome-bot/goma/gomacc: not found