Redo "Revert "Encode super calls via extra properties on prototypes.""

pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart

Index: pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart
diff --git a/pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart b/pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart
index 210899b0c8c0d96706ba3d979a6f26c0779ea7c4..b58eeaf1d1267fc4929f54aadff7aa2c889b223f 100644
--- a/pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart
+++ b/pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart
@@ -358,25 +358,6 @@ class OldEmitter implements Emitter {
             finishedClassesAccess]);
   }
 
-  List buildSplitOffAliases() {
-    if (backend.aliasedSuperMembers.isEmpty) return [];
-    return [js(r'''
-        var splitOffAliases = function(constructor) {
-          var hasOwnProperty = Object.prototype.hasOwnProperty;
-          var properties = constructor.prototype;
-          for (var member in properties) {
-            if (hasOwnProperty.call(properties, member)) {
-              var s = member.split(':');
-              if (s.length > 1) {
-                properties[s[0]] = properties[s[1]] = properties[member];
-                delete properties[member];
-              }
-            }
-          }
-        }
-      ''')];
-  }
-
   jsAst.Fun get finishClassesFunction {
     // Class descriptions are collected in a JS object.
     // 'finishClasses' takes all collected descriptions and sets up
@@ -533,11 +514,6 @@ class OldEmitter implements Emitter {
         finishedClasses[cls] = true;
 
         var superclass = pendingClasses[cls];
-        var constructor = allClasses[cls];
-
-        // Process aliased members due to super calls. We have to do this early
-        // to ensure that we also hit the object class.
-        if (#) splitOffAliases(constructor);
 
         // The superclass is only false (empty string) for the Dart Object
         // class.  The minifier together with noSuchMethod can put methods on
@@ -545,6 +521,7 @@ class OldEmitter implements Emitter {
         // that we have a string.
         if (!superclass || typeof superclass != "string") return;
         finishClass(superclass);
+        var constructor = allClasses[cls];
         var superConstructor = allClasses[superclass];
 
         if (!superConstructor)
@@ -603,7 +580,6 @@ class OldEmitter implements Emitter {
         }
       }
     }''', [finishedClassesAccess,
-           backend.aliasedSuperMembers.isNotEmpty,
            !nativeClasses.isEmpty,
            interceptorsByTagAccess,
            leafTagsAccess,
@@ -715,7 +691,6 @@ class OldEmitter implements Emitter {
     if (!needsDefineClass) return [];
     return defineClassFunction
     ..add(buildInheritFrom())
-    ..addAll(buildSplitOffAliases())
     ..add(js('$finishClassesName = #', finishClassesFunction))
     ..add(initFinishClasses);
   }