Override stub path before PreEarlyInitDBus

Otherwise install attributes are not loaded on the linux Chrome OS
build.

TEST=manual

Bug: 848615, 729596
Change-Id: I445b2b337b707822459c076058610f49f02767ab
Reviewed-on: https://chromium-review.googlesource.com/c/1264643
Commit-Queue: Roman Sorokin <rsorokin@chromium.org>
Reviewed-by: Alexei Svitkine <asvitkine@chromium.org>
Reviewed-by: Xi Han <hanxi@chromium.org>
Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599138}
2 files changed