[Boundary interfaces] Add a package file to hide boundary interfaces
am: 8858477884

Change-Id: I4a03d20d5d0af58912da2f0c932a89809ab230b1
tree: 0219fe732c173ba2dfb7c97695828abb8c27eab7
  1. src/
  2. BUILD.gn
  3. DEPS