Revert "[soong] new field in Android.bp to request APK signing V4"

This reverts commit 17d69e3484d2e74f28721e86a6554c3d0d740a51.

Reason for revert: This new field is not useful without dependencies in aosp

Test: builds
Change-Id: I87bd820cd6dbc5274ce3d28c4578381718aa805d
Merged-In: I70d6f7dc751510311b03e245b2189a76b395a49c
diff --git a/java/app_builder.go b/java/app_builder.go
index b2780bc..5e7fbe6 100644
--- a/java/app_builder.go
+++ b/java/app_builder.go
@@ -45,7 +45,7 @@
 	})
 
 func CreateAndSignAppPackage(ctx android.ModuleContext, outputFile android.WritablePath,
-	packageFile, jniJarFile, dexJarFile android.Path, certificates []Certificate, deps android.Paths, v4SignatureFile android.WritablePath) {
+	packageFile, jniJarFile, dexJarFile android.Path, certificates []Certificate, deps android.Paths) {
 
 	unsignedApkName := strings.TrimSuffix(outputFile.Base(), ".apk") + "-unsigned.apk"
 	unsignedApk := android.PathForModuleOut(ctx, unsignedApkName)
@@ -66,10 +66,10 @@
 		Implicits: deps,
 	})
 
-	SignAppPackage(ctx, outputFile, unsignedApk, certificates, v4SignatureFile)
+	SignAppPackage(ctx, outputFile, unsignedApk, certificates)
 }
 
-func SignAppPackage(ctx android.ModuleContext, signedApk android.WritablePath, unsignedApk android.Path, certificates []Certificate, v4SignatureFile android.WritablePath) {
+func SignAppPackage(ctx android.ModuleContext, signedApk android.WritablePath, unsignedApk android.Path, certificates []Certificate) {
 
 	var certificateArgs []string
 	var deps android.Paths
@@ -78,22 +78,14 @@
 		deps = append(deps, c.Pem, c.Key)
 	}
 
-	outputFiles := android.WritablePaths{signedApk}
-	var flag string = ""
-	if v4SignatureFile != nil {
-		outputFiles = append(outputFiles, v4SignatureFile)
-		flag = "--enable-v4"
-	}
-
 	ctx.Build(pctx, android.BuildParams{
 		Rule:        Signapk,
 		Description: "signapk",
-		Outputs:     outputFiles,
+		Output:      signedApk,
 		Input:       unsignedApk,
 		Implicits:   deps,
 		Args: map[string]string{
 			"certificates": strings.Join(certificateArgs, " "),
-			"flags":        flag,
 		},
 	})
 }