Squashed 'third_party/protobuf/' content from commit e35e248

Change-Id: I6cbe123d09fe50fdcad0e51466665daeee7433c7
git-subtree-dir: third_party/protobuf
git-subtree-split: e35e24800fb8d694bdeea5fd63dc7d1b14d68723
diff --git a/csharp/src/Google.Protobuf/Collections/ReadOnlyDictionary.cs b/csharp/src/Google.Protobuf/Collections/ReadOnlyDictionary.cs
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+++ b/csharp/src/Google.Protobuf/Collections/ReadOnlyDictionary.cs
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+#region Copyright notice and license

+// Protocol Buffers - Google's data interchange format

+// Copyright 2008 Google Inc.  All rights reserved.

+// https://developers.google.com/protocol-buffers/

+//

+// Redistribution and use in source and binary forms, with or without

+// modification, are permitted provided that the following conditions are

+// met:

+//

+//     * Redistributions of source code must retain the above copyright

+// notice, this list of conditions and the following disclaimer.

+//     * Redistributions in binary form must reproduce the above

+// copyright notice, this list of conditions and the following disclaimer

+// in the documentation and/or other materials provided with the

+// distribution.

+//     * Neither the name of Google Inc. nor the names of its

+// contributors may be used to endorse or promote products derived from

+// this software without specific prior written permission.

+//

+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

+#endregion

+

+using System;

+using System.Collections;

+using System.Collections.Generic;

+

+namespace Google.Protobuf.Collections

+{

+    /// <summary>

+    /// Read-only wrapper around another dictionary.

+    /// </summary>

+    internal sealed class ReadOnlyDictionary<TKey, TValue> : IDictionary<TKey, TValue>

+    {

+        private readonly IDictionary<TKey, TValue> wrapped;

+

+        public ReadOnlyDictionary(IDictionary<TKey, TValue> wrapped)

+        {

+            this.wrapped = wrapped;

+        }

+

+        public void Add(TKey key, TValue value)

+        {

+            throw new InvalidOperationException();

+        }

+

+        public bool ContainsKey(TKey key)

+        {

+            return wrapped.ContainsKey(key);

+        }

+

+        public ICollection<TKey> Keys

+        {

+            get { return wrapped.Keys; }

+        }

+

+        public bool Remove(TKey key)

+        {

+            throw new InvalidOperationException();

+        }

+

+        public bool TryGetValue(TKey key, out TValue value)

+        {

+            return wrapped.TryGetValue(key, out value);

+        }

+

+        public ICollection<TValue> Values

+        {

+            get { return wrapped.Values; }

+        }

+

+        public TValue this[TKey key]

+        {

+            get { return wrapped[key]; }

+            set { throw new InvalidOperationException(); }

+        }

+

+        public void Add(KeyValuePair<TKey, TValue> item)

+        {

+            throw new InvalidOperationException();

+        }

+

+        public void Clear()

+        {

+            throw new InvalidOperationException();

+        }

+

+        public bool Contains(KeyValuePair<TKey, TValue> item)

+        {

+            return wrapped.Contains(item);

+        }

+

+        public void CopyTo(KeyValuePair<TKey, TValue>[] array, int arrayIndex)

+        {

+            wrapped.CopyTo(array, arrayIndex);

+        }

+

+        public int Count

+        {

+            get { return wrapped.Count; }

+        }

+

+        public bool IsReadOnly

+        {

+            get { return true; }

+        }

+

+        public bool Remove(KeyValuePair<TKey, TValue> item)

+        {

+            throw new InvalidOperationException();

+        }

+

+        public IEnumerator<KeyValuePair<TKey, TValue>> GetEnumerator()

+        {

+            return wrapped.GetEnumerator();

+        }

+

+        IEnumerator IEnumerable.GetEnumerator()

+        {

+            return ((IEnumerable) wrapped).GetEnumerator();

+        }

+

+        public override bool Equals(object obj)

+        {

+            return wrapped.Equals(obj);

+        }

+

+        public override int GetHashCode()

+        {

+            return wrapped.GetHashCode();

+        }

+

+        public override string ToString()

+        {

+            return wrapped.ToString();

+        }

+    }

+}
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