Enable MA0091 and fix noncompliance

"Sender should be 'this' for instance events"

.global.editorconfig.ini

@@ -281,7 +281,7 @@ dotnet_diagnostic.MA0089.severity = error
 # Remove empty else/finally block
 dotnet_diagnostic.MA0090.severity = silent
 # Sender should be 'this' for instance events
-dotnet_diagnostic.MA0091.severity = silent
+dotnet_diagnostic.MA0091.severity = error
 # Sender should be 'null' for static events
 dotnet_diagnostic.MA0092.severity = error
 # EventArgs should not be null

src/BizHawk.Client.Common/Api/Classes/EmuClientApi.cs

@@ -55,6 +55,7 @@ namespace BizHawk.Client.Common
 
 		public int BufferWidth() => VideoProvider.BufferWidth;
 
+#pragma warning disable MA0091 // passing through `sender` is intentional
 		private void CallBeforeQuickLoad(object sender, BeforeQuickLoadEventArgs args)
 			=> BeforeQuickLoad?.Invoke(sender, args);
  
@@ -69,6 +70,7 @@ namespace BizHawk.Client.Common
  
 		private void CallStateSaved(object sender, StateSavedEventArgs args)
 			=> StateSaved?.Invoke(sender, args);
+#pragma warning restore MA0091
 
 		public void ClearAutohold() => _mainForm.ClearHolds();
 

src/BizHawk.Client.EmuHawk/CustomControls/InputRoll/InputRoll.cs

@@ -1335,10 +1335,12 @@ namespace BizHawk.Client.EmuHawk
 			}
 		}
 
+#pragma warning disable MA0091 // passing through `sender` is intentional
 		private void DoRightMouseScroll(object sender, MouseEventArgs e)
 		{
 			RightMouseScrolled?.Invoke(sender, e);
 		}
+#pragma warning restore MA0091
 
 		private void ColumnClickEvent(RollColumn/*?*/ column)
 		{
@@ -1620,6 +1622,7 @@ namespace BizHawk.Client.EmuHawk
 				Refresh();
 			}
 
+#pragma warning disable MA0091 // unorthodox, but I think this is sound --yoshi
 			if (_horizontalOrientation)
 			{
 				ColumnScroll?.Invoke(_hBar, e);
@@ -1628,6 +1631,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				RowScroll?.Invoke(_vBar, e);
 			}
+#pragma warning restore MA0091
 		}
 
 		private void HorizontalBar_ValueChanged(object sender, EventArgs e)
@@ -1637,6 +1641,7 @@ namespace BizHawk.Client.EmuHawk
 				Refresh();
 			}
 
+#pragma warning disable MA0091 // unorthodox, but I think this is sound --yoshi
 			if (_horizontalOrientation)
 			{
 				RowScroll?.Invoke(_hBar, e);
@@ -1645,6 +1650,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				ColumnScroll?.Invoke(_vBar, e);
 			}
+#pragma warning restore MA0091
 		}
 
 		private void ColumnChangedCallback()

src/BizHawk.Client.EmuHawk/MainForm.cs

@@ -4045,7 +4045,7 @@ namespace BizHawk.Client.EmuHawk
 
 					ExtToolManager.BuildToolStrip();
 
-					RomLoaded?.Invoke(null, EventArgs.Empty);
+					RomLoaded?.Invoke(this, EventArgs.Empty);
 					return true;
 				}
 				else if (Emulator.IsNull())
@@ -4059,7 +4059,7 @@ namespace BizHawk.Client.EmuHawk
 				else
 				{
 					// The ROM has been loaded by a recursive invocation of the LoadROM method.
-					RomLoaded?.Invoke(null, EventArgs.Empty);
+					RomLoaded?.Invoke(this, EventArgs.Empty);
 					return true;
 				}
 			}