Merge branch 'master' of https://github.com/unitycontainer/microsoft-dependency-injection into v5.x

Author: ENikS

src/Lifetime/InjectionSingletonLifetimeManager.cs

@@ -11,7 +11,7 @@ public class InjectionSingletonLifetimeManager : SynchronizedLifetimeManager,
         #region Fields
 
         private readonly ILifetimeContainer _container;
-        private object _value;
+        private object _value = NoValue;
 
         #endregion
 
@@ -42,12 +42,12 @@ protected override void SynchronizedSetValue(object newValue, ILifetimeContainer
         /// <param name="container">Instance of container</param>
         public override void RemoveValue(ILifetimeContainer container = null)
         {
-            if (_value == null) return;
+            if (NoValue == _value) return;
             if (_value is IDisposable disposable)
             {
                 disposable.Dispose();
             }
-            _value = null;
+            _value = NoValue;
         }
 
         protected override LifetimeManager OnCreateLifetimeManager()

src/Lifetime/InjectionTransientLifetimeManager.cs

@@ -18,20 +18,12 @@ public override void SetValue(object newValue, ILifetimeContainer container = nu
                 container?.Add(disposable);
         }
 
-        public override object GetValue(ILifetimeContainer container = null)
-        {
-            return null;
-        }
-
-        public override void RemoveValue(ILifetimeContainer container = null)
-        {
-        }
+        protected override LifetimeManager OnCreateLifetimeManager() => this;
 
-        protected override LifetimeManager OnCreateLifetimeManager()
+        public override bool InUse
         {
-            return this;
+            get => false;
+            set { }
         }
-
-        public override bool InUse { get => false; set => base.InUse = false; }
     }
 }