Export a few utility methods

Add a few utility methods to support generating TradeFed test plan in C-Suite

Test: go test .
Change-Id: I86a505068b5d5aa0f5a37b3e3a2465839a7480ef
diff --git a/java/java_test.go b/java/java_test.go
index e7776c3..30586ec 100644
--- a/java/java_test.go
+++ b/java/java_test.go
@@ -2429,3 +2429,16 @@
 		t.Errorf("Unexpected test data - expected: %q, actual: %q", expected, actual)
 	}
 }
+
+func TestDefaultInstallable(t *testing.T) {
+	ctx, _ := testJava(t, `
+		java_test_host {
+			name: "foo"
+		}
+	`)
+
+	buildOS := android.BuildOs.String()
+	module := ctx.ModuleForTests("foo", buildOS+"_common").Module().(*TestHost)
+	assertDeepEquals(t, "Default installable value should be true.", proptools.BoolPtr(true),
+		module.properties.Installable)
+}