-Use static nametable in camel case contract resolver

Src/Newtonsoft.Json.Tests/Serialization/CamelCasePropertyNamesContractResolverTests.cs

@@ -48,12 +48,17 @@ namespace Newtonsoft.Json.Tests.Serialization
         public void EnsureContractsShared()
         {
             CamelCasePropertyNamesContractResolver resolver1 = new CamelCasePropertyNamesContractResolver();
-            var contract1 = resolver1.ResolveContract(typeof(CamelCasePropertyNamesContractResolverTests));
+            var contract1 = (JsonObjectContract)resolver1.ResolveContract(typeof(CamelCasePropertyNamesContractResolverTests));
 
             CamelCasePropertyNamesContractResolver resolver2 = new CamelCasePropertyNamesContractResolver();
-            var contract2 = resolver1.ResolveContract(typeof(CamelCasePropertyNamesContractResolverTests));
+            var contract2 = (JsonObjectContract)resolver2.ResolveContract(typeof(CamelCasePropertyNamesContractResolverTests));
 
             Assert.IsTrue(ReferenceEquals(contract1, contract2));
+
+            var nt1 = resolver1.GetNameTable();
+            var nt2 = resolver2.GetNameTable();
+
+            Assert.IsTrue(ReferenceEquals(nt1, nt2));
         }
 
         [Test]

Src/Newtonsoft.Json/JsonSerializer.cs

@@ -951,7 +951,7 @@ namespace Newtonsoft.Json
                 DefaultContractResolver resolver = _contractResolver as DefaultContractResolver;
                 if (resolver != null)
                 {
-                    textReader.NameTable = resolver.NameTable;
+                    textReader.NameTable = resolver.GetNameTable();
                 }
             }
         }

Src/Newtonsoft.Json/Serialization/CamelCasePropertyNamesContractResolver.cs

@@ -68,6 +68,7 @@ namespace Newtonsoft.Json.Serialization
     public class CamelCasePropertyNamesContractResolver : DefaultContractResolver
     {
         private static readonly object TypeContractCacheLock = new object();
+        private static readonly PropertyNameTable NameTable = new PropertyNameTable();
         private static Dictionary<ResolverContractKey, JsonContract> _contractCache;
 
         /// <summary>
@@ -117,5 +118,10 @@ namespace Newtonsoft.Json.Serialization
 
             return contract;
         }
+
+        internal override PropertyNameTable GetNameTable()
+        {
+            return NameTable;
+        }
     }
 }

Src/Newtonsoft.Json/Serialization/DefaultContractResolver.cs

@@ -85,7 +85,7 @@ namespace Newtonsoft.Json.Serialization
         };
 
         private readonly object _typeContractCacheLock = new object();
-        internal readonly PropertyNameTable NameTable = new PropertyNameTable();
+        private readonly PropertyNameTable _nameTable = new PropertyNameTable();
 
         private Dictionary<Type, JsonContract> _contractCache;
 
@@ -1239,6 +1239,8 @@ namespace Newtonsoft.Json.Serialization
                 throw new JsonSerializationException("Null collection of serializable members returned.");
             }
 
+            PropertyNameTable nameTable = GetNameTable();
+
             JsonPropertyCollection properties = new JsonPropertyCollection(type);
 
             foreach (MemberInfo member in members)
@@ -1248,9 +1250,9 @@ namespace Newtonsoft.Json.Serialization
                 if (property != null)
                 {
                     // nametable is not thread-safe for multiple writers
-                    lock (NameTable)
+                    lock (nameTable)
                     {
-                        property.PropertyName = NameTable.Add(property.PropertyName);
+                        property.PropertyName = nameTable.Add(property.PropertyName);
                     }
 
                     properties.AddProperty(property);
@@ -1261,6 +1263,11 @@ namespace Newtonsoft.Json.Serialization
             return orderedProperties;
         }
 
+        internal virtual PropertyNameTable GetNameTable()
+        {
+            return _nameTable;
+        }
+
         /// <summary>
         /// Creates the <see cref="IValueProvider"/> used by the serializer to get and set values from a member.
         /// </summary>