dont call into C core to get Timespec.InfPast and Timespec.InfFuture

src/csharp/Grpc.Core.Tests/Internal/TimespecTest.cs

@@ -61,15 +61,15 @@ namespace Grpc.Core.Internal.Tests
         }
 
         [Test]
-        public void InfFuture()
+        public void InfFutureMatchesNativeValue()
         {
-            var timespec = Timespec.InfFuture;
+            Assert.AreEqual(Timespec.NativeInfFuture, Timespec.InfFuture);
         }
 
         [Test]
-        public void InfPast()
+        public void InfPastMatchesNativeValue()
         {
-            var timespec = Timespec.InfPast;
+            Assert.AreEqual(Timespec.NativeInfPast, Timespec.InfPast);
         }
 
         [Test]

src/csharp/Grpc.Core/Internal/Timespec.cs

@@ -71,7 +71,7 @@ namespace Grpc.Core.Internal
         {
             get
             {
-                return Native.gprsharp_inf_future(GPRClockType.Realtime);
+                return new Timespec(long.MaxValue, 0, GPRClockType.Realtime);
             }
         }
 
@@ -82,7 +82,7 @@ namespace Grpc.Core.Internal
         {
             get
             {
-                return Native.gprsharp_inf_past(GPRClockType.Realtime);
+                return new Timespec(long.MinValue, 0, GPRClockType.Realtime);
             }
         }
 
@@ -231,6 +231,7 @@ namespace Grpc.Core.Internal
             }
         }
 
+        // for tests only
         internal static int NativeSize
         {
             get
@@ -238,5 +239,23 @@ namespace Grpc.Core.Internal
                 return Native.gprsharp_sizeof_timespec();
             }
         }
+
+        // for tests only
+        internal static Timespec NativeInfFuture
+        {
+            get
+            {
+                return Native.gprsharp_inf_future(GPRClockType.Realtime);
+            }
+        }
+
+        // for tests only
+        public static Timespec NativeInfPast
+        {
+            get
+            {
+                return Native.gprsharp_inf_past(GPRClockType.Realtime);
+            }
+        }
     }
 }