Added Exception.Throws overload to take multiple possible messages to match

This way tests can pass in multiple possible string matches which the runtime may use as a message depending on the given platform (e.g.: MS-Runtime vs Mono)

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

@@ -2975,8 +2975,11 @@ Path '', line 1, position 1.",
             string json = @"[]";
 
             ExceptionAssert.Throws<InvalidCastException>(
-                @"Unable to cast object of type 'Newtonsoft.Json.Linq.JArray' to type 'Newtonsoft.Json.Linq.JObject'.",
-                () => { JsonConvert.DeserializeObject<JObject>(json); });
+				() => { JsonConvert.DeserializeObject<JObject>(json); },
+				new [] { 
+					"Unable to cast object of type 'Newtonsoft.Json.Linq.JArray' to type 'Newtonsoft.Json.Linq.JObject'.",
+					"Cannot cast from source type to destination type." // mono
+				});
         }
 
         [Test]
@@ -6304,18 +6307,22 @@ To fix this error either change the environment to be fully trusted, change the
         public void DeserializeDoubleFromNullString()
         {
             ExceptionAssert.Throws<ArgumentNullException>(
-                @"Value cannot be null.
-Parameter name: value",
-                () => { JsonConvert.DeserializeObject<double>(null); });
+				() => { JsonConvert.DeserializeObject<double>(null); },
+				new [] { 
+					"Value cannot be null." + Environment.NewLine + "Parameter name: value",
+					"Argument cannot be null." + Environment.NewLine + "Parameter name: value" // mono
+				});
         }
 
         [Test]
         public void DeserializeFromNullString()
         {
             ExceptionAssert.Throws<ArgumentNullException>(
-                @"Value cannot be null.
-Parameter name: value",
-                () => { JsonConvert.DeserializeObject(null); });
+				() => { JsonConvert.DeserializeObject(null); },
+				new [] { 
+					"Value cannot be null." + Environment.NewLine + "Parameter name: value",
+					"Argument cannot be null." + Environment.NewLine + "Parameter name: value" // mono
+				});
         }
 
         [Test]