jacoco correctly gathers info from APK-in-APEX

This change fixes a bug that jacoco-report-classes-all.jar does not
include info for APK-in-APEX such as the MediaProvider apk in
com.android.mediaprovider APEX.

Firstly, LOCAL_SOONG_JACOCO_REPORT_CLASSES_JAR is correctly set also for
the APKs included in APEXes. Secondly, the Make modules for the embedded
APKs are now built with soong_app_prebuilt.mk to correctly import the
jacoco file into the Make world.

Bug: 147296855
Test: execute the following command in internal master.
$ choosecombo cf_x86_phone userdebug
$ NINJA_ARGS="-t path out/target/product/vsoc_x86/jacoco-report-classes-all.jar out/target/common/obj/ETC/MediaProvider.com.android.mediaprovider_intermediates/jacoco-report-classes.jar" EMMA_INSTRUMENT=true EMMA_INSTRUMENT_FRAMEWORK=true m
The result shows that there is a path as follows:
out/target/product/vsoc_x86/jacoco-report-classes-all.jar
out/target/product/vsoc_x86/apex/com.android.mediaprovider/priv-app/MediaProvider/MediaProvider.apk
out/target/product/vsoc_x86/obj/ETC/MediaProvider.com.android.mediaprovider_intermediates/package.apk
out/target/common/obj/ETC/MediaProvider.com.android.mediaprovider_intermediates/jacoco-report-classes.jar

Change-Id: I52d11534a34eb35219bfafca4453e75a1b701c0e
diff --git a/apex/apex.go b/apex/apex.go
index 9867a7a..75a6053 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -465,6 +465,8 @@
 	requiredModuleNames       []string
 	targetRequiredModuleNames []string
 	hostRequiredModuleNames   []string
+
+	jacocoReportClassesFile android.Path // only for javalibs and apps
 }
 
 func newApexFile(ctx android.BaseModuleContext, builtFile android.Path, moduleName string, installDir string, class apexFileClass, module android.Module) apexFile {
@@ -889,7 +891,9 @@
 func apexFileForJavaLibrary(ctx android.BaseModuleContext, lib javaLibrary) apexFile {
 	dirInApex := "javalib"
 	fileToCopy := lib.DexJar()
-	return newApexFile(ctx, fileToCopy, lib.Name(), dirInApex, javaSharedLib, lib)
+	af := newApexFile(ctx, fileToCopy, lib.Name(), dirInApex, javaSharedLib, lib)
+	af.jacocoReportClassesFile = lib.JacocoReportClassesFile()
+	return af
 }
 
 func apexFileForPrebuiltEtc(ctx android.BaseModuleContext, prebuilt android.PrebuiltEtcModule, depName string) apexFile {
@@ -902,6 +906,7 @@
 	android.Module
 	Privileged() bool
 	OutputFile() android.Path
+	JacocoReportClassesFile() android.Path
 }, pkgName string) apexFile {
 	appDir := "app"
 	if aapp.Privileged() {
@@ -909,7 +914,9 @@
 	}
 	dirInApex := filepath.Join(appDir, pkgName)
 	fileToCopy := aapp.OutputFile()
-	return newApexFile(ctx, fileToCopy, aapp.Name(), dirInApex, app, aapp)
+	af := newApexFile(ctx, fileToCopy, aapp.Name(), dirInApex, app, aapp)
+	af.jacocoReportClassesFile = aapp.JacocoReportClassesFile()
+	return af
 }
 
 // Context "decorator", overriding the InstallBypassMake method to always reply `true`.