Convert `m nothing` to soong

So that it works in soong-only builds.

Fixes: 388095162
Test: m --soong-only nothing
Change-Id: I9b8b9f4f3b95524cd526476f1141d920011cd47a

2 files changed, 35 insertions, 0 deletions

diff --git a/android/Android.bp b/android/Android.bp
index bb16856dc..d27a8facf 100644
--- a/android/Android.bp
+++ b/android/Android.bp
@@ -79,6 +79,7 @@ bootstrap_go_package {
         "namespace.go",
         "neverallow.go",
         "ninja_deps.go",
+        "nothing.go",
         "notices.go",
         "onceper.go",
         "override_module.go",
diff --git a/android/nothing.go b/android/nothing.go
new file mode 100644
index 000000000..18bf85b28
--- /dev/null
+++ b/android/nothing.go
@@ -0,0 +1,34 @@
+// Copyright 2025 Google Inc. All rights reserved.
+//
+// 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
+
+func init() {
+	RegisterParallelSingletonType("nothing_singleton", nothingSingletonFactory)
+}
+
+func nothingSingletonFactory() Singleton {
+	return &nothingSingleton{}
+}
+
+type nothingSingleton struct{}
+
+func (s *nothingSingleton) GenerateBuildActions(ctx SingletonContext) {
+	rule := NewRuleBuilder(pctx, ctx)
+	rule.SetPhonyOutput()
+	rule.Command().
+		Text("echo Successfully read the makefiles.").
+		ImplicitOutput(PathForPhony(ctx, "nothing"))
+	rule.Build("nothing", "nothing")
+}