Version: 49.0.2623.87 official build checkout with official deps.
OS: Windows 8.1

GYP_DEFINES=mini_installer_official_deps=1 target_arch=x64 branding=Chrome buildtype=Official

What steps will reproduce the problem?

Build chrome official 49.0.2623.0 base_unittests

out\Release_x64\base_unittests --gtest_filter=SharedMemoryTest.UnsafeImageSection --gtest_repeat=10

Note: Google Test filter = SharedMemoryTest.UnsafeImageSection
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from SharedMemoryTest
[ RUN      ] SharedMemoryTest.UnsafeImageSection
d:\src\chrome\src\base\memory\shared_memory_unittest.cc(588): error: Value of: file_handle.IsValid()
  Actual: false
Expected: true
d:\src\chrome\src\base\memory\shared_memory_unittest.cc(592): error: Value of: section_handle.IsValid()
  Actual: false
Expected: true
d:\src\chrome\src\base\memory\shared_memory_unittest.cc(596): error: Value of: shared_memory_open.Open(kTestSectionName, true)
  Actual: false
Expected: true
[  FAILED  ] SharedMemoryTest.UnsafeImageSection (12 ms)
[----------] 1 test from SharedMemoryTest (16 ms total)

[----------] Global test environment tear-down
[==========] 1 test from 1 test case ran. (27 ms total)
[  PASSED  ] 0 tests.
[  FAILED  ] 1 test, listed below:
[  FAILED  ] SharedMemoryTest.UnsafeImageSection

 1 FAILED TEST

This bug is for me to remember to test this again on a more recent build. I just noticed this when I was building and toying with an official 49.0.2623.87 build.