BAPI: Update service API to report LaCrOS version

The LaCrOS version is determined following the same approach used for
Chrome.

BUG=b:235371788
TEST=./unit_tests

Change-Id: I0a961c6f8fc7a6dd0d5cf510380c12f8473513c0
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/4205801
Tested-by: Gilberto Contreras <gcontreras@google.com>
Commit-Queue: Gilberto Contreras <gcontreras@google.com>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Alex Klein <saklein@chromium.org>
diff --git a/api/controller/packages.py b/api/controller/packages.py
index cd79b88..feafe40 100644
--- a/api/controller/packages.py
+++ b/api/controller/packages.py
@@ -155,7 +155,9 @@
 def GetChromeVersion(input_proto, output_proto, _config):
     """Returns the chrome version."""
     build_target = controller_util.ParseBuildTarget(input_proto.build_target)
-    chrome_version = packages.determine_chrome_version(build_target)
+    chrome_version = packages.determine_package_version(
+        constants.CHROME_CP, build_target
+    )
     if chrome_version:
         output_proto.version = chrome_version
 
@@ -169,6 +171,7 @@
     output_proto.platform_version = "12438.0.0"
     output_proto.milestone_version = "78"
     output_proto.full_version = "R78-12438.0.0"
+    output_proto.lacros_version = "111.0.5550.0"
 
 
 @faux.success(_GetTargetVersionsResponse)
@@ -191,6 +194,7 @@
     output_proto.platform_version = target_versions.platform_version or ""
     output_proto.milestone_version = target_versions.milestone_version or ""
     output_proto.full_version = target_versions.full_version or ""
+    output_proto.lacros_version = target_versions.lacros_version or ""
 
 
 def _GetBuilderMetadataResponse(input_proto, output_proto, _config):