Apply apimapper instrument tool on android tests

Apimapper is a tool to instrument android tests to log potentail API calls at the run time.

The real tool is developed internally. We use a placeholder binary in
AOSP before the real tool is ready.

The tool will only take affect when the enviroment var EMMA_API_MAPPER
is set to true.

Test: m cts
Bug: 328699028

Change-Id: Iece53b8afdb9803334b7393527f4fa24e22f71a8
diff --git a/java/app.go b/java/app.go
index abd78b7..8768544 100644
--- a/java/app.go
+++ b/java/app.go
@@ -1471,7 +1471,23 @@
 	return testConfig
 }
 
+func (a *AndroidTestHelperApp) DepsMutator(ctx android.BottomUpMutatorContext) {
+	if len(a.ApexProperties.Apex_available) == 0 && ctx.Config().IsEnvTrue("EMMA_API_MAPPER") {
+		// Instrument the android_test_helper target to log potential API calls at the run time.
+		// Contact android-xts-infra team before using the environment var EMMA_API_MAPPER.
+		ctx.AddVariationDependencies(nil, staticLibTag, "apimapper-helper-device-lib")
+		a.setApiMapper(true)
+	}
+	a.AndroidApp.DepsMutator(ctx)
+}
+
 func (a *AndroidTest) DepsMutator(ctx android.BottomUpMutatorContext) {
+	if len(a.ApexProperties.Apex_available) == 0 && ctx.Config().IsEnvTrue("EMMA_API_MAPPER") {
+		// Instrument the android_test_helper target to log potential API calls at the run time.
+		// Contact android-xts-infra team before using the environment var EMMA_API_MAPPER.
+		ctx.AddVariationDependencies(nil, staticLibTag, "apimapper-helper-device-lib")
+		a.setApiMapper(true)
+	}
 	a.AndroidApp.DepsMutator(ctx)
 }