Make 'where' lazy.

sdk/lib/_internal/compiler/implementation/compile_time_constants.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 dart2js;
 
 /**
  * The [ConstantHandler] keeps track of compile-time constants,
  * initializations of global and static fields, and default values of
  * optional parameters.
@@ skipping 166 matching lines @@
                                                 definitions,
                                                 compiler);
         return evaluator.evaluate(node);
       } on CompileTimeConstantError catch (exn) {
         return null;
       }
     });
   }
 
   /**
-   * Returns a [List] of static non final fields that need to be initialized.
-   * The list must be evaluated in order since the fields might depend on each
-   * other.
+   * Returns an [Iterable] of static non final fields that need to be
+   * initialized. The fields list must be evaluated in order since they might
+   * depend on each other.
    */
-  List<VariableElement> getStaticNonFinalFieldsForEmission() {
+  Iterable<VariableElement> getStaticNonFinalFieldsForEmission() {
     return initialVariableValues.keys.where((element) {
       return element.kind == ElementKind.FIELD
           && !element.isInstanceMember()
           && !element.modifiers.isFinal();
     });
   }
 
   /**
-   * Returns a [List] of static const fields that need to be initialized. The
-   * list must be evaluated in order since the fields might depend on each
+   * Returns an [Iterable] of static const fields that need to be initialized.
+   * The fields must be evaluated in order since they might depend on each
    * other.
    */
-  List<VariableElement> getStaticFinalFieldsForEmission() {
+  Iterable<VariableElement> getStaticFinalFieldsForEmission() {
     return initialVariableValues.keys.where((element) {
       return element.kind == ElementKind.FIELD
           && !element.isInstanceMember()
           && element.modifiers.isFinal();
     });
   }
 
   List<VariableElement> getLazilyInitializedFieldsForEmission() {
     return new List<VariableElement>.from(lazyStatics);
   }
@@ skipping 605 matching lines @@
             // Use the default value.
             fieldValue = compiler.compileConstant(field);
           }
           jsNewArguments.add(fieldValue);
         },
         includeBackendMembers: true,
         includeSuperMembers: true);
     return jsNewArguments;
   }
 }