Fix a bug that design library cannot be compiled in chromium

Design library's widgets depends on v7 appcompat.

BUG=498585

Change-Id: I17fc43107a60e46f16f8e9d033a817d66db82f7e
Reviewed-on: https://chromium-review.googlesource.com/284579
Reviewed-by: Aurimas Liutikas <aurimas@chromium.org>
Commit-Queue: Aurimas Liutikas <aurimas@chromium.org>
Tested-by: Aurimas Liutikas <aurimas@chromium.org>