[tradefed] Add option to fetch build props and SPL

This CL allows the test runner to fetch build property and security
patch from cros_host.py.

BUG=b:174188466
TEST=test_that

Change-Id: If85df001576167b3a66a95ba45b12aeb988f8fc6
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/autotest/+/2591827
Tested-by: Jiyoun Ha <jiyounha@chromium.org>
Reviewed-by: Kazuhiro Inaba <kinaba@chromium.org>
Commit-Queue: Kazuhiro Inaba <kinaba@chromium.org>
Auto-Submit: Jiyoun Ha <jiyounha@chromium.org>
diff --git a/server/hosts/cros_host.py b/server/hosts/cros_host.py
index 06f59d8..079b3f0 100644
--- a/server/hosts/cros_host.py
+++ b/server/hosts/cros_host.py
@@ -1522,6 +1522,30 @@
         self.run('start powerd', ignore_status=True)
 
 
+    def _get_arc_build_info(self):
+        """Returns a dictionary mapping build properties to their values."""
+        build_info = None
+        build_path_arcvm = '/usr/share/arcvm/properties/build.prop'
+        build_path_arc = '/usr/share/arc/properties/build.prop'
+        if self.path_exists(build_path_arcvm):
+            build_info = utils.parse_cmd_output('cat ' + build_path_arcvm,
+                                                run_method=self.run)
+        elif self.path_exists(build_path_arc):
+            build_info = utils.parse_cmd_output('cat ' + build_path_arc,
+                                                run_method=self.run)
+        if build_info == None:
+            logging.error('Failed to find build property info in device.')
+            return
+        return build_info
+
+    def _get_arc_primary_abi(self):
+        """Returns the primary abi of the host."""
+        return self._get_arc_build_info().get('ro.product.cpu.abi')
+
+    def _get_arc_security_patch(self):
+        """Returns the security patch of the host."""
+        return self._get_arc_build_info().get('ro.build.version.security_patch')
+
     def _get_lsb_release_content(self):
         """Return the content of lsb-release file of host."""
         return self.run(