Remove embedder locator from analysis context

pkg/analyzer/lib/source/embedder.dart

 // Copyright (c) 2015, 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 analyzer.source.embedder;
 
 import 'dart:collection' show HashMap;
 import 'dart:core' hide Resource;
 
 import 'package:analyzer/file_system/file_system.dart';
@@ skipping 169 matching lines @@
 /// existence of an `_embedder.yaml` file. If the file contains a top level
 /// YamlMap, it will be added to the [embedderYamls] map.
 class EmbedderYamlLocator {
   static const String EMBEDDER_FILE_NAME = '_embedder.yaml';
 
   /// Map from package's library directory to the parsed YamlMap.
   final Map<Folder, YamlMap> embedderYamls = new HashMap<Folder, YamlMap>();
 
   EmbedderYamlLocator(Map<String, List<Folder>> packageMap) {
     if (packageMap != null) {
-      refresh(packageMap);
+      _processPackageMap(packageMap);
     }
   }
 
   /// Programatically add an _embedder.yaml mapping.
   void addEmbedderYaml(Folder libDir, String embedderYaml) {
     _processEmbedderYaml(libDir, embedderYaml);
   }
 
   void refresh(Map<String, List<Folder>> packageMap) {
     // Clear existing.
     embedderYamls.clear();
-    if (packageMap == null) {
-      return;
+    if (packageMap != null) {
+      _processPackageMap(packageMap);
     }
-    packageMap.forEach(_processPackage);
   }
 
   /// Given the yaml for an embedder ([embedderYaml]) and a folder
   /// ([libDir]), setup the uri mapping.
   void _processEmbedderYaml(Folder libDir, String embedderYaml) {
     YamlNode yaml;
     try {
       yaml = loadYaml(embedderYaml);
     } catch (_) {
       return;
     }
     if (yaml is! YamlMap) {
       return;
     }
     embedderYamls[libDir] = yaml;
   }
 
   /// Given a package [name] and a list of folders ([libDirs]),
   /// add any found `_embedder.yaml` files.
   void _processPackage(String name, List<Folder> libDirs) {
     for (Folder libDir in libDirs) {
       String embedderYaml = _readEmbedderYaml(libDir);
       if (embedderYaml != null) {
         _processEmbedderYaml(libDir, embedderYaml);
       }
     }
   }
 
+  void _processPackageMap(Map<String, List<Folder>> packageMap) {
+    packageMap.forEach(_processPackage);
+  }
+
   /// Read the contents of [libDir]/[EMBEDDER_FILE_NAME] as a string.
   /// Returns null if the file doesn't exist.
   String _readEmbedderYaml(Folder libDir) {
     File file = libDir.getChild(EMBEDDER_FILE_NAME);
     try {
       return file.readAsStringSync();
     } on FileSystemException {
       // File can't be read.
       return null;
     }
   }
 }