More freezing tidy-up; generated code in next commit.

csharp/src/Google.Protobuf/Collections/RepeatedField.cs

@@ -40,7 +40,7 @@ namespace Google.Protobuf.Collections
 {
     /// <summary>
     /// The contents of a repeated field: essentially, a collection with some extra
-    /// restrictions (no null values) and capabilities (deep cloning and freezing).
+    /// restrictions (no null values) and capabilities (deep cloning).
     /// </summary>
     /// <typeparam name="T">The element type of the repeated field.</typeparam>
     public sealed class RepeatedField<T> : IList<T>, IList, IDeepCloneable<RepeatedField<T>>, IEquatable<RepeatedField<T>>
@@ -65,7 +65,6 @@ namespace Google.Protobuf.Collections
         public RepeatedField<T> Clone()
         {
             RepeatedField<T> clone = new RepeatedField<T>();
-            // Clone is implicitly *not* frozen, even if this object is.
             if (array != EmptyArray)
             {
                 clone.array = (T[])array.Clone();

src/google/protobuf/compiler/csharp/csharp_message.cc

@@ -134,9 +134,7 @@ void MessageGenerator::Generate(io::Printer* printer) {
     "pbr::MessageDescriptor pb::IMessage.Descriptor {\n"
     "  get { return Descriptor; }\n"
     "}\n"
-    "\n"
-    "private bool _frozen = false;\n"
-    "public bool IsFrozen { get { return _frozen; } }\n\n");
+    "\n");
 
   // Parameterless constructor and partial OnConstruction method.
   printer->Print(