Changing SpawnChild to return a struct.

base/android/global_object_registry.h

+// Copyright 2017 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.
+
+#ifndef BASE_ANDROID_GLOBAL_OBJECT_REGISTRY_H_
+#define BASE_ANDROID_GLOBAL_OBJECT_REGISTRY_H_
+
+#include <stdint.h>
+
+#include <map>
+
+#include "base/android/scoped_java_ref.h"
+#include "build/build_config.h"
+
+namespace base {
+namespace android {
+
+// The GlobalObjectRegistry is a singleton object used to store and retrieve
+// Java objects from native code. It is useful during child process creation and
+// is used somehow similarlty to the way GlobalDescriptors is used to deal with
+// file descriptors.
+// It might make sense in the future to merge this class and GlobalDescriptors
+// into a unique ProcessInitiContext class.
+class BASE_EXPORT GlobalObjectRegistry final {
+ public:
+  typedef uint32_t Key;
+
+  // Returns the singleton instance of GlobalObjectRegistry.
+  static GlobalObjectRegistry* GetInstance();
+
+  // Stores |java_object| and associates it with |key|.
+  void Set(Key key, const JavaRef<jobject>& java_object);
+
+  ScopedJavaLocalRef<jobject> Take(Key key);
+
+ private:
+  GlobalObjectRegistry();
+
+  std::map<Key, ScopedJavaGlobalRef<jobject>> mappings_;
+
+  DISALLOW_COPY_AND_ASSIGN(GlobalObjectRegistry);
+};
+
+}  // namespace android
+}  // namespace base
+
+#endif  // BASE_ANDROID_GLOBAL_OBJECT_REGISTRY_H_