Remove unused ctor param on SimpleGDIPDisplayManager

fixes 1f70320

Author: YoshiRulz

src/BizHawk.Client.Common/DisplayManager/SimpleGDIPDisplayManager.cs

@@ -20,7 +20,7 @@ private SimpleGDIPDisplayManager(Config config, IEmulator emuCore, IGL_GDIPlus g
 				new GDIPlusGuiRenderer(glImpl))
 			{}
 
-		public SimpleGDIPDisplayManager(Config config, IEmulator emuCore, Func<(int Width, int Height)> getVirtualSize)
+		public SimpleGDIPDisplayManager(Config config, IEmulator emuCore)
 			: this(config, emuCore, new IGL_GDIPlus()) {}
 
 		protected override void ActivateGraphicsControlContext() {}

src/BizHawk.Tests.Testroms/DummyFrontend.cs

@@ -153,7 +153,7 @@ public DummyFrontend(ClassInitCallbackDelegate init)
 			CoreAsDebuggable = Core.CanDebug() ? Core.AsDebuggable() : null;
 			CoreAsMemDomains = Core.HasMemoryDomains() ? Core.AsMemoryDomains() : null;
 			_coreAsVP = core.AsVideoProvider();
-			_dispMan = new(_config, core, () => (_coreAsVP!.VirtualWidth, _coreAsVP.VirtualHeight));
+			_dispMan = new(_config, core);
 		}
 
 		public void Dispose()