Roll src/third_party/gtest/gtest from 16f637fbf4ff to 4fe3307fb2d9

https://chromium.googlesource.com/external/github.com/google/googletest/+log/16f637fbf4ff..4fe3307fb2d9

Drive-by: third_party/ninja should be src/third_party/ninja.

Change-Id: Ic2e27709a1622c541258ee815fca52f35fc7eeab
2 files changed