Fix fplutil to search in correct place for gtest and gmock in Gerrit.
Fix fplutil to search in correct place for gtest and gmock in Gerrit.

Fix bug where wrong location was checked for gmock. Add search location for
gtest.
PiperOrigin-RevId: 139950971
Change-Id: I258e624a718b91116cb385e189c4e2e4483736a7

google/fplutil,google/fplutil,google/fplutil,google/fplutil,google/fplutil,google/fplutil