Use art_defaults in libnative*, for consistency.

Also change to //art:__submodules__ for consistent internal visibility, and
some TODO comment corrections.

Test: m WITH_TIDY=1
Test: build & boot
Test: atest art/libnativeloader/test (no new errors, but existing ones on arm64 - b/142896688)
Test: (atest art/libnativebridge/tests doesn't work at all, but that's not new - b/142897320)
Bug: 137364733
Bug: 133140750
Change-Id: If9ddb5a597eea3606342c3625dcdb3bcf5d19041
4 files changed