JavaScript Binary expressions not subclass of Call

sdk/lib/_internal/compiler/implementation/ssa/codegen.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of ssa;
 
 class SsaCodeGeneratorTask extends CompilerTask {
 
   final JavaScriptBackend backend;
 
@@ skipping 777 matching lines @@
                 expressions = sequence.expressions;
               } else {
                 expressions = <js.Expression>[jsInitialization];
               }
               bool canTransformToVariableDeclaration = true;
               for (js.Expression expression in expressions) {
                 bool expressionIsVariableAssignment = false;
                 if (expression is js.Assignment) {
                   js.Assignment assignment = expression;
                   if (assignment.leftHandSide is js.VariableUse &&
-                      assignment.compoundTarget == null) {
+                      !assignment.isCompound) {
                     expressionIsVariableAssignment = true;
                   }
                 }
                 if (!expressionIsVariableAssignment) {
                   canTransformToVariableDeclaration = false;
                   break;
                 }
               }
               if (canTransformToVariableDeclaration) {
                 List<js.VariableInitialization> inits =
@@ skipping 1872 matching lines @@
   js.PropertyAccess accessHelper(String name) {
     Element helper = compiler.findHelper(name);
     if (helper == null) {
       // For mocked-up tests.
       return js.js('(void 0).$name');
     }
     world.registerStaticUse(helper);
     return backend.namer.elementAccess(helper);
   }
 }