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

sdk/lib/_internal/libraries.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.
 
 library libraries;
 
 /**
  * A bit flag used by [LibraryInfo] indicating that a library is used by dart2js
  */
 const int DART2JS_PLATFORM = 1;
@@ skipping 12 matching lines @@
 const Map<String, LibraryInfo> LIBRARIES = const <LibraryInfo> {
 
   "collection": const LibraryInfo(
       "collection/collection.dart",
       implementation: true),
 
   "core": const LibraryInfo(
       "core/core.dart",
       dart2jsPatchPath: "_internal/compiler/implementation/lib/core_patch.dart"),
 
-  "coreimpl": const LibraryInfo(
-      "coreimpl/coreimpl.dart",
-      implementation: true,
-      dart2jsPatchPath: "_internal/compiler/implementation/lib/coreimpl_patch.dart"),
-
   "crypto": const LibraryInfo(
       "crypto/crypto.dart"),
 
   "html": const LibraryInfo(
       "html/dartium/html_dartium.dart",
       category: "Client",
       dart2jsPath: "html/dart2js/html_dart2js.dart"),
 
   "io": const LibraryInfo(
       "io/io.dart",
@@ skipping 90 matching lines @@
    * Bit flags indicating which platforms consume this library.
    * See [DART2JS_LIBRARY] and [VM_LIBRARY].
    */
   final int platforms;
 
   /**
    * True if the library contains implementation details for another library.
    * The implication is that these libraries are less commonly used
    * and that tools like Dart Editor should not show these libraries
    * in a list of all libraries unless the user specifically asks the tool to
-   * do so. (E.g. "coreimpl" contains implementation for the "core" library).
+   * do so.
    */
   final bool implementation;
 
   const LibraryInfo(this.path, {
                     this.category: "Shared",
                     this.dart2jsPath,
                     this.dart2jsPatchPath,
                     this.implementation: false,
                     this.documented: true,
                     this.platforms: DART2JS_PLATFORM | VM_PLATFORM});
 
   bool get isDart2jsLibrary => (platforms & DART2JS_PLATFORM) != 0;
   bool get isVmLibrary => (platforms & VM_PLATFORM) != 0;
 }