After upgrading my tree I got:
[10 processes, 461/6771 @ 12.4/s : 37.155s ] CC obj/third_party/fontconfig/fontconfig/fccache.o
FAILED: obj/third_party/fontconfig/fontconfig/fccache.o 
../../third_party/llvm-build-no-asserts/Release+No+Asserts/bin/clang -MMD -MF obj/third_party/fontconfig/fontconfig/fccache.o.d -DHAVE_CONFIG_H -DFC_CACHEDIR=\"/var/cache/fontconfig\" -DFC_TEMPLATEDIR=\"/usr/share/fontconfig/conf.avail\" -DFONTCONFIG_PATH=\"/etc/fonts\" -DV8_DEPRECATION_WARNINGS -DUSE_UDEV -DUSE_AURA=1 -DUSE_GLIB=1 -DUSE_NSS_CERTS=1 -DUSE_X11=1 -DFULL_SAFE_BROWSING -DSAFE_BROWSING_CSD -DSAFE_BROWSING_DB_LOCAL -DCHROMIUM_BUILD -DFIELDTRIAL_TESTING_ENABLED -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -DCOMPONENT_BUILD -DCR_LIBCXX_REVISION=332543 -DCR_LIBCXXABI_REVISION=331450 -D_DEBUG -DDYNAMIC_ANNOTATIONS_ENABLED=1 -DWTF_USE_DYNAMIC_ANNOTATIONS=1 -D_GLIBCXX_DEBUG=1 -DFT_CONFIG_CONFIG_H=\"freetype-custom-config/ftconfig.h\" -DFT_CONFIG_MODULES_H=\"freetype-custom-config/ftmodule.h\" -DFT_CONFIG_OPTIONS_H=\"freetype-custom-config/ftoption.h\" -DPDFIUM_REQUIRED_MODULES -DU_USING_ICU_NAMESPACE=0 -DU_ENABLE_DYLOAD=0 -DICU_UTIL_DATA_IMPL=ICU_UTIL_DATA_FILE -DUCHAR_TYPE=uint16_t -I../../third_party/fontconfig/include -I../../third_party/fontconfig/include/src -I../.. -Igen -I../../third_party/fontconfig/src -I../../third_party/freetype/include -I../../third_party/freetype/src/include -I../../third_party/harfbuzz-ng/src/src -I../../third_party/libxml/src/include -I../../third_party/libxml/linux/include -I../../third_party/icu/source/common -I../../third_party/icu/source/i18n -I../../third_party/zlib -Wno-non-literal-null-conversion -Wno-pointer-bool-conversion -fno-strict-aliasing --param=ssp-buffer-size=4 -fstack-protector -Wno-builtin-macro-redefined -D__DATE__= -D__TIME__= -D__TIMESTAMP__= -funwind-tables -fPIC -B../../third_party/binutils/Linux_x64/Release/bin -pthread -fcolor-diagnostics -fmerge-all-constants -Xclang -mllvm -Xclang -instcombine-lower-dbg-declare=0 -no-canonical-prefixes -fcomplete-member-pointers -m64 -march=x86-64 -O0 -fno-omit-frame-pointer -g2 -gsplit-dwarf -ggnu-pubnames -fvisibility=hidden -Xclang -load -Xclang ../../third_party/llvm-build-no-asserts/Release+No+Asserts/lib/libFindBadConstructs.so -Xclang -add-plugin -Xclang find-bad-constructs -Xclang -plugin-arg-find-bad-constructs -Xclang enforce-in-thirdparty-webkit -Xclang -plugin-arg-find-bad-constructs -Xclang check-enum-max-value -Xclang -plugin-arg-find-bad-constructs -Xclang check-ipc -Wheader-hygiene -Wstring-conversion -Wtautological-overlap-compare -Werror -Wall -Wno-unused-variable -Wno-missing-field-initializers -Wno-unused-parameter -Wno-c++11-narrowing -Wno-covered-switch-default -Wno-unneeded-internal-declaration -Wno-undefined-var-template -Wno-address-of-packed-member -Wno-nonportable-include-path -Wno-user-defined-warnings -Wno-unused-lambda-capture -Wno-null-pointer-arithmetic -Wno-enum-compare-switch -Wno-ignored-pragma-optimize -DLIBXML_STATIC= -std=gnu11 -c ../../third_party/fontconfig/src/src/fccache.c -o obj/third_party/fontconfig/fontconfig/fccache.o
../../third_party/fontconfig/src/src/fccache.c:42:10: fatal error: 'uuid/uuid.h' file not found