General uncontroversial cleanup:

- Made private methods static where possible (runtime can elide checking the object for null).
- Declared attribute classes as sealed (allows reflection on attributes to complete faster).
- Moved some static cctor's into field initializers (static cctor's are slower than static field initializers).
- Made classes static if they contained only static methods (can't create instances of useless objects).
- Use inferable Exts.Lazy and not new Lazy<T>().
- Added required STAThread attribute to CrashDialog.
- Removed unused parameters in private methods.
- Added Serializable attribute to exceptions.
- Added parameter name in calls to ArgumentNullException.
- Use of as operator instead of is + cast.
- Changed (x as Foo).Bar anti-pattern into ((Foo)x).Bar. Results in sensible cast exceptions on error rather than null dereferences.
- Removed unused method in NullShader.

OpenRA.Game/Scripting/ScriptContext.cs

@@ -34,13 +34,13 @@ namespace OpenRA.Scripting
 	}
 
 	// For traitinfos that provide actor / player commands
-	public class ScriptPropertyGroupAttribute : Attribute
+	public sealed class ScriptPropertyGroupAttribute : Attribute
 	{
 		public readonly string Category;
 		public ScriptPropertyGroupAttribute(string category) { Category = category; }
 	}
 
-	public class ScriptActorPropertyActivityAttribute : Attribute { }
+	public sealed class ScriptActorPropertyActivityAttribute : Attribute { }
 
 	public abstract class ScriptActorProperties
 	{
@@ -75,7 +75,7 @@ namespace OpenRA.Scripting
 		}
 	}
 
-	public class ScriptGlobalAttribute : Attribute
+	public sealed class ScriptGlobalAttribute : Attribute
 	{
 		public readonly string Name;
 		public ScriptGlobalAttribute(string name) { Name = name; }

OpenRA.Game/Scripting/ScriptMemberExts.cs

@@ -49,23 +49,23 @@ namespace OpenRA.Scripting
 
 		public static string LuaDocString(this MemberInfo mi)
 		{
-			if (mi is MethodInfo)
+			var methodInfo = mi as MethodInfo;
+			if (methodInfo != null)
 			{
-				var methodInfo = mi as MethodInfo;
 				var parameters = methodInfo.GetParameters().Select(pi => pi.LuaDocString());
 				return "{0} {1}({2})".F(methodInfo.ReturnType.LuaDocString(), mi.Name, parameters.JoinWith(", "));
 			}
 
-			if (mi is PropertyInfo)
+			var propertyInfo = mi as PropertyInfo;
+			if (propertyInfo != null)
 			{
-				var pi = mi as PropertyInfo;
 				var types = new List<string>();
-				if (pi.GetGetMethod() != null)
+				if (propertyInfo.GetGetMethod() != null)
 					types.Add("get;");
-				if (pi.GetSetMethod() != null)
+				if (propertyInfo.GetSetMethod() != null)
 					types.Add("set;");
 
-				return "{0} {1} {{ {2} }}".F(pi.PropertyType.LuaDocString(), mi.Name, types.JoinWith(" "));
+				return "{0} {1} {{ {2} }}".F(propertyInfo.PropertyType.LuaDocString(), mi.Name, types.JoinWith(" "));
 			}
 
 			return "Unknown field: {0}".F(mi.Name);

OpenRA.Game/Scripting/ScriptMemberWrapper.cs

@@ -51,7 +51,7 @@ namespace OpenRA.Scripting
 			if (!IsMethod)
 				throw new LuaException("Trying to invoke a ScriptMemberWrapper that isn't a method!");
 
-			var mi = Member as MethodInfo;
+			var mi = (MethodInfo)Member;
 			var pi = mi.GetParameters();
 
 			object[] clrArgs = new object[pi.Length];
@@ -71,7 +71,7 @@ namespace OpenRA.Scripting
 					throw new LuaException("Unable to convert parameter {0} to {1}".F(i, pi[i].ParameterType.Name));
 			}
 
-			var ret = (Member as MethodInfo).Invoke(Target, clrArgs);
+			var ret = (mi.Invoke(Target, clrArgs));
 			return ret.ToLuaValue(context);
 		}