Skeleton for IVmTethering service with flag guarding

This reverts commit f9676878292a49caa03e5270c3be2769b029db60.

Bug: 340376953
Test: adb shell /apex/com.android.virt/bin/vm run-microdroid --network-supported

Change-Id: I9c859dd43e7ba7c852a71afce8f36ca10477ad24
diff --git a/virtualizationservice/aidl/Android.bp b/virtualizationservice/aidl/Android.bp
index fb89772..bca4512 100644
--- a/virtualizationservice/aidl/Android.bp
+++ b/virtualizationservice/aidl/Android.bp
@@ -86,6 +86,26 @@
 }
 
 aidl_interface {
+    name: "android.system.vmtethering",
+    srcs: ["android/system/vmtethering/**/*.aidl"],
+    unstable: true,
+    backend: {
+        java: {
+            sdk_version: "module_current",
+            apex_available: [
+                "com.android.virt",
+            ],
+        },
+        rust: {
+            enabled: true,
+            apex_available: [
+                "com.android.virt",
+            ],
+        },
+    },
+}
+
+aidl_interface {
     name: "android.system.virtualmachineservice",
     srcs: ["android/system/virtualmachineservice/**/*.aidl"],
     imports: [
diff --git a/virtualizationservice/aidl/android/system/vmtethering/IVmTethering.aidl b/virtualizationservice/aidl/android/system/vmtethering/IVmTethering.aidl
new file mode 100644
index 0000000..732a515
--- /dev/null
+++ b/virtualizationservice/aidl/android/system/vmtethering/IVmTethering.aidl
@@ -0,0 +1,24 @@
+/*
+ * Copyright 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.system.vmtethering;
+
+interface IVmTethering {
+    /**
+     * Start VM tethering to provide external network to VM.
+     */
+    void enableVmTethering();
+}