Use 'stem' to override APK name

When android_app.stem is set, use it as the APK name like other module
types.

Bug: 193504286
Test: m (soong test)
Change-Id: I4c95b77be382cff3cfecaf6ce38f99aed9f3238f

java/androidmk.go

@@ -433,8 +433,10 @@ func (a *AndroidApp) getOverriddenPackages() []string {
 	if len(a.appProperties.Overrides) > 0 {
 		overridden = append(overridden, a.appProperties.Overrides...)
 	}
-	if a.Name() != a.installApkName {
+	// When APK name is overridden via PRODUCT_PACKAGE_NAME_OVERRIDES
-		overridden = append(overridden, a.Name())
+	// ensure that the original name is overridden.
+	if a.Stem() != a.installApkName {
+		overridden = append(overridden, a.Stem())
 	}
 	return overridden
 }

java/app.go

@@ -621,7 +621,7 @@ func (a *AndroidApp) generateAndroidBuildActions(ctx android.ModuleContext) {
 	a.aapt.useEmbeddedDex = Bool(a.appProperties.Use_embedded_dex)
 
 	// Check if the install APK name needs to be overridden.
-	a.installApkName = ctx.DeviceConfig().OverridePackageNameFor(a.Name())
+	a.installApkName = ctx.DeviceConfig().OverridePackageNameFor(a.Stem())
 
 	if ctx.ModuleName() == "framework-res" {
 		// framework-res.apk is installed as system/framework/framework-res.apk
@@ -1006,6 +1006,7 @@ func (a *AndroidTest) FixTestConfig(ctx android.ModuleContext, testConfig androi
 	command := rule.Command().BuiltTool("test_config_fixer").Input(testConfig).Output(fixedConfig)
 	fixNeeded := false
 
+	// Auto-generated test config uses `ModuleName` as the APK name. So fix it if it is not the case.
 	if ctx.ModuleName() != a.installApkName {
 		fixNeeded = true
 		command.FlagWithArg("--test-file-name ", a.installApkName+".apk")

java/app_test.go

@@ -1707,7 +1707,7 @@ func TestPackageNameOverride(t *testing.T) {
 			},
 		},
 		{
-			name: "overridden",
+			name: "overridden via PRODUCT_PACKAGE_NAME_OVERRIDES",
 			bp: `
 				android_app {
 					name: "foo",
@@ -1722,6 +1722,22 @@ func TestPackageNameOverride(t *testing.T) {
 				"out/soong/target/product/test_device/system/app/bar/bar.apk",
 			},
 		},
+		{
+			name: "overridden via stem",
+			bp: `
+				android_app {
+					name: "foo",
+					srcs: ["a.java"],
+					sdk_version: "current",
+					stem: "bar",
+				}
+			`,
+			packageNameOverride: "",
+			expected: []string{
+				"out/soong/.intermediates/foo/android_common/bar.apk",
+				"out/soong/target/product/test_device/system/app/bar/bar.apk",
+			},
+		},
 	}
 
 	for _, test := range testCases {