Change some MainForm event handlers to delegate typed properties

makes encapsulation easier

src/BizHawk.Client.EmuHawk/MainForm.Designer.cs

@@ -3230,8 +3230,6 @@
 			this.Load += new System.EventHandler(this.MainForm_Load);
 			this.Shown += new System.EventHandler(this.MainForm_Shown);
 			this.Enter += new System.EventHandler(this.MainForm_Enter);
-			this.MouseClick += new System.Windows.Forms.MouseEventHandler(this.MainForm_MouseClick);
-			this.MouseMove += new System.Windows.Forms.MouseEventHandler(this.MainForm_MouseMove);
 			this.Resize += new System.EventHandler(this.MainForm_Resize);
 			this.MainformMenu.ResumeLayout(false);
 			this.MainformMenu.PerformLayout();

src/BizHawk.Client.EmuHawk/MainForm.Events.cs

@@ -2613,25 +2613,11 @@ namespace BizHawk.Client.EmuHawk
 			AutohideCursor(false);
 		}
 
-		public void MainForm_MouseWheel(object sender, MouseEventArgs e)
-		{
-			MouseWheelTracker += e.Delta;
-		}
+		public MouseEventHandler MainForm_MouseWheel { get; }
 
-		public void MainForm_MouseMove(object sender, MouseEventArgs e)
-		{
-			AutohideCursor(false);
-		}
+		public MouseEventHandler MainForm_MouseMove { get; }
 
-		public void MainForm_MouseClick(object sender, MouseEventArgs e)
-		{
-			AutohideCursor(false);
-			if (Config.ShowContextMenu && e.Button == MouseButtons.Right)
-			{
-				MainFormContextMenu.Show(
-					PointToScreen(new Point(e.X, e.Y + MainformMenu.Height)));
-			}
-		}
+		public MouseEventHandler MainForm_MouseClick { get; }
 
 		private void MainForm_Resize(object sender, EventArgs e)
 		{

src/BizHawk.Client.EmuHawk/MainForm.cs

@@ -371,6 +371,17 @@ namespace BizHawk.Client.EmuHawk
 				Sound?.StartSound();
 			};
 
+			MouseClick += MainForm_MouseClick = (sender, e) =>
+			{
+				AutohideCursor(false);
+				if (Config.ShowContextMenu && e.Button == MouseButtons.Right)
+				{
+					MainFormContextMenu.Show(PointToScreen(new Point(e.X, e.Y + MainformMenu.Height)));
+				}
+			};
+			MouseMove += MainForm_MouseMove = (sender, e) => AutohideCursor(false);
+			MainForm_MouseWheel = (sender, e) => MouseWheelTracker += e.Delta;
+
 			Input.Instance.MainFormInputAllowedCallback = yieldAlt => {
 				// the main form gets input
 				if (ActiveForm == this)

src/BizHawk.Client.EmuHawk/PresentationPanel.cs

@@ -28,9 +28,9 @@ namespace BizHawk.Client.EmuHawk
 			// pass through these events to the form. we might need a more scalable solution for mousedown etc. for zapper and whatnot.
 			// http://stackoverflow.com/questions/547172/pass-through-mouse-events-to-parent-control (HTTRANSPARENT)
 			GraphicsControl.MouseDoubleClick += HandleFullscreenToggle;
-			GraphicsControl.MouseClick += (o, e) => _mainForm.MainForm_MouseClick(o, e);
-			GraphicsControl.MouseMove += (o, e) => _mainForm.MainForm_MouseMove(o, e);
-			GraphicsControl.MouseWheel += (o, e) => _mainForm.MainForm_MouseWheel(o, e);
+			GraphicsControl.MouseClick += _mainForm.MainForm_MouseClick;
+			GraphicsControl.MouseMove += _mainForm.MainForm_MouseMove;
+			GraphicsControl.MouseWheel += _mainForm.MainForm_MouseWheel;
 		}
 
 		private bool _isDisposed;