cromo: Create a standalone ebuild for system_api

system_api is required by a lot of platform2 packages. We need it to be in a
standalone ebuild in order for other packages to depend on it.

This package installs the common headers and compiles the protobufs into static
libraries.

BUG=chromium:386223
TEST=FEATURES=test emerge-amd64-generic platform2.
TEST=trybot run on daisy, link, duck, x86-mario.
TEST=trybot run on lumpy-incremental-release.

CQ-DEPEND=CL:204594

Change-Id: Ia4bce7a7b9876a6a31c37a36bafc49978f6dd9d0
Reviewed-on: https://chromium-review.googlesource.com/204591
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Tested-by: Bertrand Simonnet <bsimonnet@chromium.org>
Commit-Queue: Bertrand Simonnet <bsimonnet@chromium.org>
1 file changed