Add a "native_support" service.

services/native_support/main.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/message_loop/message_loop.h"
+#include "base/threading/sequenced_worker_pool.h"
+#include "mojo/application/application_runner_chromium.h"
+#include "mojo/public/c/system/main.h"
+#include "mojo/public/cpp/application/application_connection.h"
+#include "mojo/public/cpp/application/application_delegate.h"
+#include "mojo/public/cpp/application/interface_factory.h"
+#include "mojo/services/native_support/public/interfaces/process.mojom.h"
+#include "services/native_support/process_impl.h"
+
+namespace native_support {
+
+// TODO(vtl): Having to manually choose an arbitrary number is dumb.
+const size_t kMaxWorkerThreads = 16;
+
+class NativeSupportApp : public mojo::ApplicationDelegate,
+                         public mojo::InterfaceFactory<Process> {
+ public:
+  NativeSupportApp() {}
+  ~NativeSupportApp() override {
+    if (worker_pool_)
+      worker_pool_->Shutdown();
+  }
+
+ private:
+  // |mojo::ApplicationDelegate| override:
+  bool ConfigureIncomingConnection(
+      mojo::ApplicationConnection* connection) override {
+    connection->AddService<Process>(this);
+    return true;
+  }
+
+  // |InterfaceFactory<Process>| implementation:
+  void Create(mojo::ApplicationConnection* connection,
+              mojo::InterfaceRequest<Process> request) override {
+    if (!worker_pool_) {
+      worker_pool_ = new base::SequencedWorkerPool(kMaxWorkerThreads,
+                                                   "NativeSupportWorker");
+    }
+    new ProcessImpl(worker_pool_, connection, request.Pass());
+  }
+
+  scoped_refptr<base::SequencedWorkerPool> worker_pool_;
+
+  DISALLOW_COPY_AND_ASSIGN(NativeSupportApp);
+};
+
+}  // namespace native_support
+
+MojoResult MojoMain(MojoHandle application_request) {
+  mojo::ApplicationRunnerChromium runner(
+      new native_support::NativeSupportApp());
+  // We need an I/O message loop, since we'll want to watch FDs.
+  runner.set_message_loop_type(base::MessageLoop::TYPE_IO);
+  return runner.Run(application_request);
+}