chunk 2: remaining non-audio non-NewImport assets

Assets/GooglePlayPlugins/com.google.play.common/Runtime/Scripts/Internal/PlayAsyncOperationImpl.cs

@@ -0,0 +1,60 @@
+// Copyright 2019 Google LLC
+//
+// 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
+//
+//     https://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.
+
+using System;
+
+namespace Google.Play.Common.Internal
+{
+    /// <summary>
+    /// Provides implementation for <see cref="PlayAsyncOperation{TResult,TError}"/>.
+    /// </summary>
+    public abstract class PlayAsyncOperationImpl<TResult, TError> : PlayAsyncOperation<TResult, TError>
+    {
+        private TResult _result;
+
+        public override event Action<PlayAsyncOperation<TResult, TError>> Completed
+        {
+            add
+            {
+                if (IsDone)
+                {
+                    value.Invoke(this);
+                    return;
+                }
+
+                base.Completed += value;
+            }
+            remove { base.Completed -= value; }
+        }
+
+        public void SetResult(TResult result)
+        {
+            _result = result;
+            IsDone = true;
+            InvokeCompletedEvent();
+        }
+
+        public void SetError(TError errorCode)
+        {
+            Error = errorCode;
+            IsDone = true;
+            InvokeCompletedEvent();
+        }
+
+        protected override TResult GetResultImpl()
+        {
+            return _result;
+        }
+    }
+}