Add Lazy<T>(T value) ctor to ref

src/System.Runtime/ref/System.Runtime.cs

@@ -1202,6 +1202,7 @@ public partial interface IProgress<in T>
     public partial class Lazy<T>
     {
         public Lazy() { }
+        public Lazy(T value) { }
         public Lazy(bool isThreadSafe) { }
         public Lazy(System.Func<T> valueFactory) { }
         public Lazy(System.Func<T> valueFactory, bool isThreadSafe) { }

src/System.Runtime/tests/System/LazyTests.cs

@@ -19,6 +19,18 @@ public static void Ctor()
             VerifyLazy(lazyObject, 0, true);
         }
 
+        [Theory]
+        [InlineData(21)]
+        [InlineData(366.58)]
+        [InlineData("hello")]
+        public static void Ctor_T_PreInitialized<T>(T value)
+        {
+            var lazyObject = new Lazy<T>(value);
+
+            Assert.True(lazyObject.IsValueCreated);
+            Assert.Equal(value, lazyObject.Value);
+        }
+
         [Theory]
         [InlineData(true)]
         [InlineData(false)]