Move Snake Egg-specific logic out of Bank

Author: x-sheep

src/puzzle/Bank.js

@@ -268,9 +268,6 @@ pzpr.classmgr.makeCommon({
 		},
 
 		isNoop: function() {
-			if (this.num === null) {
-				return false;
-			}
 			return this.old === this.num;
 		},
 

src/variety/snakeegg.js

@@ -373,6 +373,13 @@
 		isBankEdit: true,
 		disInputHatena: true,
 
+		isNoop: function() {
+			if (this.num === null) {
+				return false;
+			}
+			return this.old === this.num;
+		},
+
 		isModify: function(lastope) {
 			if (
 				lastope.isBankEdit &&