Have `make` report a failing gtest run as a top-level target.

Before, if an individual gtest such (as
`test-art-host-gtest-output_stream_test64`) was invoked as
`make`'s top-level target and failing, `make` would not
report it as such through its exit status (it would be 0
whatever the result). However, when run as part of a
compound test target (such as
`test-art-host-gtest-output_stream_test` or
`test-art-host-gtest`), `make` would actually report this
test's (and maybe others') failure with a non-zero exit
status. This CL forces `make` to report a non-zero exit
status in the former case without breaking the latter one.

Test: Amend a gtest such as compiler/linker/output_stream_test.cc
    to make it artificially fail, and run it with:
      make test-art-host-gtest-output_stream_test
      make test-art-host-gtest-output_stream_test64
Bug: 31755702

Change-Id: Icbb6fef592f14d73808576e7fcb0e9d7079ec9a2
1 file changed