Remove ReturnEngineToPool method from factory as it's no longer needed

Author: Daniel15

src/React.Core/IJavaScriptEngineFactory.cs

@@ -26,11 +26,5 @@ public interface IJavaScriptEngineFactory
 		/// </summary>
 		/// <returns>The JavaScript engine</returns>
 		PooledJsEngine GetEngine();
-
-		/// <summary>
-		/// Returns an engine to the pool so it can be reused
-		/// </summary>
-		/// <param name="engine">Engine to return</param>
-		void ReturnEngineToPool(PooledJsEngine engine);
 	}
 }

src/React.Core/JavaScriptEngineFactory.cs

@@ -229,20 +229,6 @@ public virtual PooledJsEngine GetEngine()
 			return _pool.GetEngine();
 		}
 
-		/// <summary>
-		/// Returns an engine to the pool so it can be reused
-		/// </summary>
-		/// <param name="engine">Engine to return</param>
-		public virtual void ReturnEngineToPool(PooledJsEngine engine)
-		{
-			// This could be called from ReactEnvironment.Dispose if that class is disposed after 
-			// this class. Let's just ignore this if it's disposed.
-			if (!_disposed)
-			{
-				engine.Dispose();
-			}
-		}
-
 		/// <summary>
 		/// Gets a factory for the most appropriate JavaScript engine for the current environment.
 		/// The first functioning JavaScript engine with the lowest priority will be used.

src/React.Core/ReactEnvironment.cs

@@ -400,7 +400,7 @@ public void ReturnEngineToPool()
 		{
 			if (_engineFromPool.IsValueCreated)
 			{
-				_engineFactory.ReturnEngineToPool(_engineFromPool.Value);
+				_engineFromPool.Value.Dispose();
 				_engineFromPool = new Lazy<PooledJsEngine>(() => _engineFactory.GetEngine());
 			}
 		}