copy JNI from AAR files to android_app APK

JNI libs present in AAR files are ignored in the build. If those
libraries are necessary, they must be manually extracted and a
prebuilt_cc_library module must be created for them. Instead, we can
extract these libraries and copy them to an output APK as part of the build.

Bug: 228848794
Test: created android_app that depends on an android_library_import with
  JNI embedded, and verified that .so libs are present in APK
Test: created android_app that depends on an android_library which
  depends on android_library_import with JNI embedded, and verified
  that .so libs are present in APK
Test: verified that multiple .so's from a single architecture are copied
  to APK
Test: verified that the absence of a jni/<arch> folder or files in the
  folder will cause the Ninja action to error
Change-Id: I242a862d7bd881f7a4a8c23493924d8fe441ea25
diff --git a/java/app.go b/java/app.go
index 23a9816..afef334 100755
--- a/java/app.go
+++ b/java/app.go
@@ -472,14 +472,14 @@
 	return a.dexJarFile.PathOrNil()
 }
 
-func (a *AndroidApp) jniBuildActions(jniLibs []jniLib, ctx android.ModuleContext) android.WritablePath {
+func (a *AndroidApp) jniBuildActions(jniLibs []jniLib, prebuiltJniPackages android.Paths, ctx android.ModuleContext) android.WritablePath {
 	var jniJarFile android.WritablePath
-	if len(jniLibs) > 0 {
+	if len(jniLibs) > 0 || len(prebuiltJniPackages) > 0 {
 		a.jniLibs = jniLibs
 		if a.shouldEmbedJnis(ctx) {
 			jniJarFile = android.PathForModuleOut(ctx, "jnilibs.zip")
 			a.installPathForJNISymbols = a.installPath(ctx)
-			TransformJniLibsToJar(ctx, jniJarFile, jniLibs, a.useEmbeddedNativeLibs(ctx))
+			TransformJniLibsToJar(ctx, jniJarFile, jniLibs, prebuiltJniPackages, a.useEmbeddedNativeLibs(ctx))
 			for _, jni := range jniLibs {
 				if jni.coverageFile.Valid() {
 					// Only collect coverage for the first target arch if this is a multilib target.
@@ -623,8 +623,8 @@
 
 	dexJarFile := a.dexBuildActions(ctx)
 
-	jniLibs, certificateDeps := collectAppDeps(ctx, a, a.shouldEmbedJnis(ctx), !Bool(a.appProperties.Jni_uses_platform_apis))
-	jniJarFile := a.jniBuildActions(jniLibs, ctx)
+	jniLibs, prebuiltJniPackages, certificateDeps := collectAppDeps(ctx, a, a.shouldEmbedJnis(ctx), !Bool(a.appProperties.Jni_uses_platform_apis))
+	jniJarFile := a.jniBuildActions(jniLibs, prebuiltJniPackages, ctx)
 
 	if ctx.Failed() {
 		return
@@ -724,9 +724,10 @@
 
 func collectAppDeps(ctx android.ModuleContext, app appDepsInterface,
 	shouldCollectRecursiveNativeDeps bool,
-	checkNativeSdkVersion bool) ([]jniLib, []Certificate) {
+	checkNativeSdkVersion bool) ([]jniLib, android.Paths, []Certificate) {
 
 	var jniLibs []jniLib
+	var prebuiltJniPackages android.Paths
 	var certificates []Certificate
 	seenModulePaths := make(map[string]bool)
 
@@ -775,6 +776,10 @@
 			return shouldCollectRecursiveNativeDeps
 		}
 
+		if info, ok := ctx.OtherModuleProvider(module, JniPackageProvider).(JniPackageInfo); ok {
+			prebuiltJniPackages = append(prebuiltJniPackages, info.JniPackages...)
+		}
+
 		if tag == certificateTag {
 			if dep, ok := module.(*AndroidAppCertificate); ok {
 				certificates = append(certificates, dep.Certificate)
@@ -786,7 +791,7 @@
 		return false
 	})
 
-	return jniLibs, certificates
+	return jniLibs, prebuiltJniPackages, certificates
 }
 
 func (a *AndroidApp) WalkPayloadDeps(ctx android.ModuleContext, do android.PayloadDepsCallback) {