Convert robolectric_test's module-info.json to song

This produces this diff, which I beleive is beneign:
https://paste.googleplex.com/4846726910050304

Bug: 389720048
Test: diff'd module-info.json
Change-Id: I531644d208a0a9d0fb2166d158f77e671554e5d8
diff --git a/java/robolectric.go b/java/robolectric.go
index ff0c850..ed3fc9a 100644
--- a/java/robolectric.go
+++ b/java/robolectric.go
@@ -261,6 +261,19 @@
 		setExtraJavaInfo(ctx, r, javaInfo)
 		android.SetProvider(ctx, JavaInfoProvider, javaInfo)
 	}
+
+	moduleInfoJSON := r.javaLibraryModuleInfoJSON(ctx)
+	if _, ok := r.testConfig.(android.WritablePath); ok {
+		moduleInfoJSON.AutoTestConfig = []string{"true"}
+	}
+	if r.testConfig != nil {
+		moduleInfoJSON.TestConfig = append(moduleInfoJSON.TestConfig, r.testConfig.String())
+	}
+	if len(r.testProperties.Test_suites) > 0 {
+		moduleInfoJSON.CompatibilitySuites = append(moduleInfoJSON.CompatibilitySuites, r.testProperties.Test_suites...)
+	} else {
+		moduleInfoJSON.CompatibilitySuites = append(moduleInfoJSON.CompatibilitySuites, "null-suite")
+	}
 }
 
 func generateSameDirRoboTestConfigJar(ctx android.ModuleContext, outputFile android.ModuleOutPath) {