Make 'where' lazy.

sdk/lib/_internal/compiler/implementation/js_backend/emitter.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 js_backend;
 
 /**
  * A function element that represents a closure call. The signature is copied
  * from the given element.
  */
@@ skipping 1211 matching lines @@
         CodeBuffer getterBuffer = new CodeBuffer();
         getterBuffer.add(
             "function($joined) { return $getter.$closureCallName($joined); }");
         defineInstanceMember(invocationName, getterBuffer);
       }
     }
   }
 
   void emitStaticNonFinalFieldInitializations(CodeBuffer buffer) {
     ConstantHandler handler = compiler.constantHandler;
-    List<VariableElement> staticNonFinalFields =
+    Iterable<VariableElement> staticNonFinalFields =
         handler.getStaticNonFinalFieldsForEmission();
     for (Element element in staticNonFinalFields) {
       buffer.add('$isolateProperties.${namer.getName(element)} = ');
       compiler.withCurrentElement(element, () {
           Constant initialValue = handler.getInitialValueFor(element);
           writeConstantToBuffer(initialValue, buffer);
         });
       buffer.add(';\n');
     }
   }
@@ skipping 418 matching lines @@
 const String HOOKS_API_USAGE = """
 // Generated by dart2js, the Dart to JavaScript compiler.
 // The code supports the following hooks:
 // dartPrint(message)   - if this function is defined it is called
 //                        instead of the Dart [print] method.
 // dartMainRunner(main) - if this function is defined, the Dart [main]
 //                        method will not be invoked directly.
 //                        Instead, a closure that will invoke [main] is
 //                        passed to [dartMainRunner].
 """;