Add `data_native_bins` property to java_test_host

When multiple os/arch variants are supported, java_test_host could not
find a matching arch due to java having arch:common, whereas native
binaries support a specific architecture. This change adds the property
`data_native_bins` in order to support binaries with the appropriate
os/arch variants.

Test: m FirmwareDtboVerification with data_native_bins
Test: forrest
Bug: 153848038
Change-Id: I45adebff0fde2811d5ef5620c697b97b768c951f
diff --git a/python/builder.go b/python/builder.go
index 36baecd..dc2d1f1 100644
--- a/python/builder.go
+++ b/python/builder.go
@@ -91,7 +91,7 @@
 
 	if !embeddedLauncher {
 		// the path of stub_template_host.txt from source tree.
-		template := android.PathForSource(ctx, stubTemplateHost)
+		template := android.PathForSource(ctx, StubTemplateHost)
 		implicits = append(implicits, template)
 
 		// intermediate output path for __main__.py