First attempt at using profile 259 for Google.Protobuf.

This requires .NET 4.5, and there are a few compatibility changes required around reflection.
Creating a PR from this to see how our CI systems handle it. Will want to add more documentation,
validation and probably tests before merging.

This is in aid of issue #590.

2 files changed, 8 insertions, 5 deletions

diff --git a/csharp/src/Google.Protobuf/Collections/MapField.cs b/csharp/src/Google.Protobuf/Collections/MapField.cs
index 9ca5104d..68f2f1cc 100644
--- a/csharp/src/Google.Protobuf/Collections/MapField.cs
+++ b/csharp/src/Google.Protobuf/Collections/MapField.cs
@@ -35,6 +35,7 @@ using System;
 using System.Collections;
 using System.Collections.Generic;
 using System.Linq;
+using Google.Protobuf.Compatibility;
 
 namespace Google.Protobuf.Collections
 {
@@ -74,7 +75,7 @@ namespace Google.Protobuf.Collections
         /// <param name="allowNullValues">Whether null values are permitted in the map or not.</param>
         public MapField(bool allowNullValues)
         {
-            if (allowNullValues && typeof(TValue).IsValueType && Nullable.GetUnderlyingType(typeof(TValue)) == null)
+            if (allowNullValues && typeof(TValue).IsValueType() && Nullable.GetUnderlyingType(typeof(TValue)) == null)
             {
                 throw new ArgumentException("allowNullValues", "Non-nullable value types do not support null values");
             }
diff --git a/csharp/src/Google.Protobuf/Collections/RepeatedField.cs b/csharp/src/Google.Protobuf/Collections/RepeatedField.cs
index 9bab41ea..ccd1a9bb 100644
--- a/csharp/src/Google.Protobuf/Collections/RepeatedField.cs
+++ b/csharp/src/Google.Protobuf/Collections/RepeatedField.cs
@@ -29,10 +29,12 @@
 // (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 Google.Protobuf.Reflection;
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using Google.Protobuf.Compatibility;
 
 namespace Google.Protobuf.Collections
 {
@@ -88,7 +90,7 @@ namespace Google.Protobuf.Collections
             uint tag = input.LastTag;
             var reader = codec.ValueReader;
             // Value types can be packed or not.
-            if (typeof(T).IsValueType && WireFormat.GetTagWireType(tag) == WireFormat.WireType.LengthDelimited)
+            if (typeof(T).IsValueType() && WireFormat.GetTagWireType(tag) == WireFormat.WireType.LengthDelimited)
             {
                 int length = input.ReadLength();
                 if (length > 0)
@@ -119,7 +121,7 @@ namespace Google.Protobuf.Collections
                 return 0;
             }
             uint tag = codec.Tag;
-            if (typeof(T).IsValueType && WireFormat.GetTagWireType(tag) == WireFormat.WireType.LengthDelimited)
+            if (typeof(T).IsValueType() && WireFormat.GetTagWireType(tag) == WireFormat.WireType.LengthDelimited)
             {
                 int dataSize = CalculatePackedDataSize(codec);
                 return CodedOutputStream.ComputeRawVarint32Size(tag) +
@@ -165,7 +167,7 @@ namespace Google.Protobuf.Collections
             }
             var writer = codec.ValueWriter;
             var tag = codec.Tag;
-            if (typeof(T).IsValueType && WireFormat.GetTagWireType(tag) == WireFormat.WireType.LengthDelimited)
+            if (typeof(T).IsValueType() && WireFormat.GetTagWireType(tag) == WireFormat.WireType.LengthDelimited)
             {
                 // Packed primitive type
                 uint size = (uint)CalculatePackedDataSize(codec);