Handle most qualified sends.

pkg/compiler/lib/src/resolution/access_semantics.dart

 // Copyright (c) 2015, 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.
 
 // TODO(johnniwinther): Temporarily copied from analyzer2dart. Merge when
 // we shared code with the analyzer and this semantic visitor is complete.
 
 /**
  * Code for classifying the semantics of identifiers appearing in a Dart file.
  */
 library dart2js.access_semantics;
 
 import '../constants/expressions.dart';
 import '../elements/elements.dart';
 import '../dart_types.dart';
 
 /// Enum representing the different kinds of destinations which a property
 /// access or method or function invocation might refer to.
 enum AccessKind {
+  /// The destination of the conditional access is an instance method, property,
+  /// or field of a class, and thus must be determined dynamically.
+  CONDITIONAL_DYNAMIC_PROPERTY,
+
   /// The destination of the access is an instance method, property, or field
   /// of a class, and thus must be determined dynamically.
   DYNAMIC_PROPERTY,
 
   // TODO(johnniwinther): Split these cases into captured and non-captured
   // local access.
   /// The destination of the access is a function that is defined locally within
   /// an enclosing function or method.
   LOCAL_FUNCTION,
 
@@ skipping 219 matching lines @@
     return sb.toString();
   }
 }
 
 
 class DynamicAccess extends AccessSemantics {
   final target;
 
   DynamicAccess.dynamicProperty(this.target)
       : super._(AccessKind.DYNAMIC_PROPERTY);
+
+  DynamicAccess.ifNotNullProperty(this.target)
+      : super._(AccessKind.CONDITIONAL_DYNAMIC_PROPERTY);
 }
 
 class ConstantAccess extends AccessSemantics {
   final ConstantExpression constant;
 
   ConstantAccess(AccessKind kind, this.constant)
       : super._(kind);
 
   ConstantAccess.classTypeLiteral(this.constant)
       : super._(AccessKind.CLASS_TYPE_LITERAL);
@@ skipping 256 matching lines @@
 
   RedirectingFactoryConstructorAccessSemantics(
       ConstructorAccessKind kind,
       Element element,
       DartType type,
       this.effectiveTargetSemantics)
       : super(kind, element, type);
 }