UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.96 Safari/537.36

Steps to reproduce the problem:
1. Follow steps from https://chromium.googlesource.com/chromium/src/+/lkgr/headless/README.md
2.  Get duplicate symbol error

What is the expected behavior?
Build headless example

What went wrong?
uplicate symbol __ZN6device16PowerSaveBlockerD2Ev in:
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_mac.o
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_ozone.o
duplicate symbol __ZN6device16PowerSaveBlockerD1Ev in:
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_mac.o
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_ozone.o
duplicate symbol __ZN6device16PowerSaveBlockerD0Ev in:
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_mac.o
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_ozone.o
duplicate symbol __ZTVN6device16PowerSaveBlockerE in:
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_mac.o
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_ozone.o
duplicate symbol __ZN6device16PowerSaveBlockerC2ENS0_20PowerSaveBlockerTypeENS0_6ReasonERKNSt3__112basic_stringIcNS3_11char_traitsIcEENS3_9allocatorIcEEEE13scoped_refptrIN4base19SequencedTaskRunnerEESC_INSD_22SingleThreadTaskRunnerEE in:
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_mac.o
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_ozone.o
duplicate symbol __ZN6device16PowerSaveBlockerC1ENS0_20PowerSaveBlockerTypeENS0_6ReasonERKNSt3__112basic_stringIcNS3_11char_traitsIcEENS3_9allocatorIcEEEE13scoped_refptrIN4base19SequencedTaskRunnerEESC_INSD_22SingleThreadTaskRunnerEE in:
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_mac.o
    obj/device/power_save_blocker/power_save_blocker/power_save_blocker_ozone.o
ld: 6 duplicate symbols for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Traceback (most recent call last):
  File "../../build/toolchain/mac/linker_driver.py", line 229, in <module>
    Main(sys.argv)
  File "../../build/toolchain/mac/linker_driver.py", line 79, in Main
    subprocess.check_call(compiler_driver_args)
  File "/usr/local/Cellar/python/2.7.12_2/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 541, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['../../third_party/llvm-build/Release+Asserts/bin/clang++', '-shared', '-Wl,-install_name,@rpath/libpower_save_blocker.dylib', '-stdlib=libc++', '-arch', 'x86_64', '-Werror', '-isysroot', '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.12.sdk', '-mmacosx-version-min=10.9', '-Wl,-ObjC', '-Wl,-rpath,@loader_path/.', '-Wl,-rpath,@loader_path/../../..', '-o', './libpower_save_blocker.dylib', '-Wl,-filelist,./libpower_save_blocker.dylib.rsp', '-framework', 'CoreFoundation', '-framework', 'IOKit', './libbase.dylib']' returned non-zero exit status 1

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Does this work in other browsers? N/A

Chrome version: 58.0.3029.96  Channel: dev
OS Version: OS X 10.11.6
Flash Version: