This looks like a build configuration error. Assigning to troopers.

FAILED: test_data/chrome/test/data/unit/framework_unittest.gtestjs gen/chrome/test/data/unit/framework_unittest-gen.cc 
C:/b/depot_tools/python276_bin/python.exe ../../tools/gypv8sh.py ./v8_shell.exe ../../chrome/third_party/mock4js/mock4js.js ../../chrome/test/data/webui/test_api.js ../../chrome/test/base/js2gtest.js unit --external=y ../../chrome/test/data/unit/framework_unittest.gtestjs chrome/test/data/unit/framework_unittest.gtestjs gen/chrome/test/data/unit/framework_unittest-gen.cc test_data/chrome/test/data/unit/framework_unittest.gtestjs
Traceback (most recent call last):

  File "../../tools/gypv8sh.py", line 84, in <module>

    sys.exit(main())

  File "../../tools/gypv8sh.py", line 66, in main

    cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, bufsize=0)

  File "C:\b\depot_tools\python276_bin\lib\subprocess.py", line 709, in __init__

    errread, errwrite)

  File "C:\b\depot_tools\python276_bin\lib\subprocess.py", line 957, in _execute_child

    startupinfo)

WindowsError: [Error 216] This version of %1 is not compatible with the version of Windows you're running. Check your computer's system information to see whether you need a x86 (32-bit) or x64 (64-bit) version of the program, and then contact the software publisher