Updates from internal chrome_cleaner repo

* Add a hook to override the command line of test_main.cc.
chrome_cleaner_unittests has an empty implementation. Other internal
test executables that use test_main.cc use this to add flags to the
commandline.

* Add more accessors to engine_resources.h to reduce hardcoding.

* Move the dummy engine resources and signatures to their own build
targets.

* Remove unused MatchingOptions::find_incomplete_matches.

* Remove unused StartScanning and StartCleanup methods in
MainDialogAPI.

* Make test binaries into console apps.

* Allow import_util.py to work outside the source tree.

* Cleanups to deps and includes.

* Alphabetize test/BUILD.gn so it can be diffed against the internal
version more easily during upstreaming.

R=csharp

Bug: 830892
Change-Id: I263aabf02a467df231e3c227ea6f01328b9212d3
Reviewed-on: https://chromium-review.googlesource.com/1207171
Reviewed-by: Chris Sharp <csharp@chromium.org>
Reviewed-by: Ryan Hamilton <rch@chromium.org>
Reviewed-by: Mike West <mkwst@chromium.org>
Commit-Queue: Chris Sharp <csharp@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589625}
29 files changed