Make selector registration in the resolver and code generator more explicit.

tests/compiler/dart2js/unparser_test.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.
 
 #import('dart:uri');
 #import('parser_helper.dart');
 #import("../../../lib/compiler/compiler.dart");
 #import("../../../lib/compiler/implementation/tree/tree.dart");
 
 testUnparse(String statement) {
@@ skipping 176 matching lines @@
   // Class member of typedef-ed function type.
   // Maybe typedef should be included in the result too, but it
   // works fine without it.
   testDart2Dart(
     'main(){new A((arg){});}typedef void foofunc(arg);'
     'class A{A(foofunc this.handler);final foofunc handler;}');
 }
 
 testGetSet() {
   // Top-level get/set.
-  testDart2Dart('get foo(){return 5;}set foo(arg){}main(){foo; foo=5;}');
+  testDart2Dart('set foo(arg){}get foo(){return 5;}main(){foo; foo=5;}');
   // Field get/set.
   testDart2Dart('main(){var a=new A(); a.foo; a.foo=5;}'
       'class A{set foo(a){}get foo(){return 5;}}');
   // Typed get/set.
   testDart2Dart('String get foo(){return "a";}main(){foo;}');
 }
 
 testFactoryConstructor() {
   testDart2Dart('main(){new A.fromFoo();}class A{A.fromFoo();}');
   // Now more complicated, with normal constructor and factory parameters.
@@ skipping 199 matching lines @@
   testGetSet();
   testFactoryConstructor();
   testAbstractClass();
   testConflictSendsRename();
   testNoConflictSendsRename();
   testConflictLibraryClassRename();
   testDefaultClassWithArgs();
   testClassExtendsWithArgs();
   testStaticInvocation();
 }