Move Arrays, Collections and Maps into a new library, dart:collections.

lib/collection/collection_sources.gypi

Index: lib/collection/collection_sources.gypi
diff --git a/runtime/lib/scalarlist_sources.gypi b/lib/collection/collection_sources.gypi
similarity index 65%
copy from runtime/lib/scalarlist_sources.gypi
copy to lib/collection/collection_sources.gypi
index cb7c3ddd8f98026c38308515c96d38df7d944d63..d7fcc266501687d679087af14d6e98472ef4a4af 100644
--- a/runtime/lib/scalarlist_sources.gypi
+++ b/lib/collection/collection_sources.gypi
@@ -2,12 +2,12 @@
 # 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.
 
-# Sources visible via dart:scalarlist library.
-
+# This file contains all sources for the dart:collection library.
 {
   'sources': [
-    'byte_array.cc',
-    'byte_array.dart',
+    'arrays.dart',
+    'collections.dart',
+    'maps.dart',
   ],
 }