Move JSSyntaxRegExp to core as a private member. This removes the last refrences to dart:coreimpl.

runtime/lib/byte_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.
 
 patch class Int8List {
   /* patch */ factory Int8List(int length) {
     return new _Int8Array(length);
   }
 
   /* patch */ factory Int8List.view(ByteArray array,
@@ skipping 166 matching lines @@
     throw new UnsupportedError(
         "Cannot add to a non-extendable array");
   }
 
   void addAll(Collection value) {
     throw new UnsupportedError(
         "Cannot add to a non-extendable array");
   }
 
   void sort([Comparator compare = Comparable.compare]) {
-    coreSort(this, compare);
+    _Sort.sort(this, compare);
   }
 
   int indexOf(element, [int start = 0]) {
     return Arrays.indexOf(this, element, start, this.length);
   }
 
   int lastIndexOf(element, [int start = null]) {
     if (start == null) start = length - 1;
     return Arrays.lastIndexOf(this, element, start);
   }
@@ skipping 1457 matching lines @@
     throw new UnsupportedError(
         "Cannot add to a non-extendable array");
   }
 
   void addAll(Collection value) {
     throw new UnsupportedError(
         "Cannot add to a non-extendable array");
   }
 
   void sort([Comparator compare = Comparable.compare]) {
-    coreSort(this, compare);
+    _Sort.sort(this, compare);
   }
 
   int indexOf(element, [int start = 0]) {
     return Arrays.indexOf(this, element, start, this.length);
   }
 
   int lastIndexOf(element, [int start = null]) {
     if (start == null) start = length - 1;
     return Arrays.lastIndexOf(this, element, start);
   }
@@ skipping 735 matching lines @@
     }
     _rangeCheck(this.length, start, length);
     return _array.subByteArray(_offset + start, length);
   }
 
   static const int _BYTES_PER_ELEMENT = 8;
   final ByteArray _array;
   final int _offset;
   final int _length;
 }