Move relevance constants for use in plugins

pkg/analyzer_plugin/lib/utilities/completion/relevance.dart

+// Copyright (c) 2017, 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.
+
+//
+// Constant values used for relevance values when creating completion
+// suggestions in Dart code.
+//
+
+const int DART_RELEVANCE_COMMON_USAGE = 1200;
+const int DART_RELEVANCE_DEFAULT = 1000;
+const int DART_RELEVANCE_HIGH = 2000;
+const int DART_RELEVANCE_INCREMENT = 100;
+const int DART_RELEVANCE_INHERITED_ACCESSOR = 1057;
+const int DART_RELEVANCE_INHERITED_FIELD = 1058;
+const int DART_RELEVANCE_INHERITED_METHOD = 1057;
+const int DART_RELEVANCE_KEYWORD = 1055;
+const int DART_RELEVANCE_LOCAL_ACCESSOR = 1057;
+const int DART_RELEVANCE_LOCAL_FIELD = 1058;
+const int DART_RELEVANCE_LOCAL_FUNCTION = 1056;
+const int DART_RELEVANCE_LOCAL_METHOD = 1057;
+const int DART_RELEVANCE_LOCAL_TOP_LEVEL_VARIABLE = 1056;
+const int DART_RELEVANCE_LOCAL_VARIABLE = 1059;
+const int DART_RELEVANCE_LOW = 500;
+const int DART_RELEVANCE_NAMED_PARAMETER = 1060;
+const int DART_RELEVANCE_PARAMETER = 1059;