NativeBridge: add "linked namespace" semantic corresponding to linker

For dynamic linking perspective, semantics of NativeBridge needs to
align with dynamic linker. This patch adds "linked namespace" semantic
which shares some libraries from one namespace to another.

Bug: 37123321
Test: Fugu: netflix, play movies, youtube
Test: make test-art-host-run-test-115-native-bridge

cherry picked from commit e8fb11df

Change-Id: I71ce1dde19d61363d5eb9731fd4795a8c315b3a0