Some code cleanups in arrays, fix rangeCheck (issue 2899).

runtime/lib/growable_array.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.
 
 class GrowableObjectArray<T> implements List<T> {
   factory GrowableObjectArray._uninstantiable() {
     throw const UnsupportedOperationException(
         "GrowableObjectArray can only be allocated by the VM");
   }
 
@@ skipping 35 matching lines @@
                 start + length,
                 old_length - start);
     for (int i = start; i < start + length; i++) {
       this[i] = initialValue;
     }
   }
 
   List<T> getRange(int start, int length) {
     if (length == 0) return [];
     Arrays.rangeCheck(this, start, length);
-    List list = new List<T>();
+    List list = new GrowableObjectArray<T>.withCapacity(length);
     list.length = length;
     Arrays.copy(this, start, list, 0, length);
     return list;
   }
 
   factory GrowableObjectArray() {
     var data = new ObjectArray<T>(4);
     return new GrowableObjectArray<T>.fromObjectArray(data);
   }
 
@@ skipping 102 matching lines @@
     for (int i = 0; i < length; i++) {
       f(this[i]);
     }
   }
 
   Collection map(f(T element)) {
     return Collections.map(this,
                            new GrowableObjectArray.withCapacity(length), f);
   }
 
-  Dynamic reduce(Dynamic initialValue,
-                 Dynamic combine(Dynamic previousValue, T element)) {
+  reduce(initialValue, combine(previousValue, T element)) {
     return Collections.reduce(this, initialValue, combine);
   }
 
   Collection<T> filter(bool f(T element)) {
     return Collections.filter(this, new GrowableObjectArray<T>(), f);
   }
 
   bool every(bool f(T element)) {
     return Collections.every(this, f);
   }
@@ skipping 37 matching lines @@
   T next() {
     if (!hasNext()) {
       throw const NoMoreElementsException();
     }
     return _array[_pos++];
   }
 
   final GrowableObjectArray<T> _array;
   int _pos;
 }