fixes #427, static fields emitted outside the scope of their class

test/codegen/expect/collection/priority_queue.js

 dart_library.library('collection/priority_queue', null, /* Imports */[
   'dart/_runtime',
   'dart/core',
   'dart/collection'
 ], /* Lazy imports */[
 ], function(exports, dart, core, collection) {
   'use strict';
   let dartx = dart.dartx;
   const PriorityQueue$ = dart.generic(function(E) {
     class PriorityQueue extends core.Object {}
@@ skipping 206 matching lines @@
         toList: [core.List$(E), []],
         toSet: [core.Set$(E), []],
         [_add]: [dart.void, [E]],
         [_locate]: [core.int, [E]],
         [_removeLast]: [E, []],
         [_bubbleUp]: [dart.void, [E, core.int]],
         [_bubbleDown]: [dart.void, [E, core.int]],
         [_grow]: [dart.void, []]
       })
     });
+    HeapPriorityQueue._INITIAL_CAPACITY = 7;
     return HeapPriorityQueue;
   });
   let HeapPriorityQueue = HeapPriorityQueue$();
-  HeapPriorityQueue._INITIAL_CAPACITY = 7;
   const __CastType0$ = dart.generic(function(E) {
     const __CastType0 = dart.typedef('__CastType0', () => dart.functionType(core.int, [E, E]));
     return __CastType0;
   });
   let __CastType0 = __CastType0$();
   // Exports:
   exports.PriorityQueue$ = PriorityQueue$;
   exports.PriorityQueue = PriorityQueue;
   exports.HeapPriorityQueue$ = HeapPriorityQueue$;
   exports.HeapPriorityQueue = HeapPriorityQueue;
 });