Use declared variables to select the correct configuration for resolution

pkg/analyzer/lib/context/declared_variables.dart

 // Copyright (c) 2014, 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.
 
 library analyzer.context.declared_variables;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/constant/value.dart';
 import 'package:analyzer/src/dart/constant/value.dart';
@@ skipping 17 matching lines @@
   Iterable<String> get variableNames => _declaredVariables.keys;
 
   /**
    * Define a variable with the given [name] to have the given [value].
    */
   void define(String name, String value) {
     _declaredVariables[name] = value;
   }
 
   /**
+   * Return the raw string value of the variable with the given [name],
+   * or `null` of the variable is not defined.
+   */
+  String get(String name) => _declaredVariables[name];
+
+  /**
    * Return the value of the variable with the given [name] interpreted as a
    * 'boolean' value. If the variable is not defined (or [name] is `null`), a
    * DartObject representing "unknown" is returned. If the value cannot be
    * parsed as a boolean, a DartObject representing 'null' is returned. The
    * [typeProvider] is the type provider used to find the type 'bool'.
    */
   DartObject getBool(TypeProvider typeProvider, String name) {
     String value = _declaredVariables[name];
     if (value == null) {
       return new DartObjectImpl(typeProvider.boolType, BoolState.UNKNOWN_VALUE);
@@ skipping 36 matching lines @@
    */
   DartObject getString(TypeProvider typeProvider, String name) {
     String value = _declaredVariables[name];
     if (value == null) {
       return new DartObjectImpl(
           typeProvider.stringType, StringState.UNKNOWN_VALUE);
     }
     return new DartObjectImpl(typeProvider.stringType, new StringState(value));
   }
 }