Use manifest merger in Soong

Move the manifest merger config to Soong, and use it to merge
manifests of static dependencies of android_library and android_app
modules.

Bug: 110848854
Test: m checkbuild
Change-Id: Ib89e1f1a52a8b76157e4e0348baf42800412df0d
Merged-In: Ib89e1f1a52a8b76157e4e0348baf42800412df0d
Merged-In: I5d055ce63b8371db500f8868fb73ab3604b8c24a

java/config/makevars.go

@@ -73,4 +73,8 @@ func makeVarsProvider(ctx android.MakeVarsContext) {
 	ctx.Strict("EXTRACT_JAR_PACKAGES", "${ExtractJarPackagesCmd}")
 
 	ctx.Strict("MANIFEST_FIXER", "${ManifestFixerCmd}")
+
+	ctx.Strict("ANDROID_MANIFEST_MERGER_DEPS", "${ManifestMergerJars}")
+	ctx.Strict("ANDROID_MANIFEST_MERGER",
+		"${JavaCmd} -classpath ${ManifestMergerClasspath} com.android.manifmerger.Merger")
 }