Initial Bazel file resolver support.

pkg/analyzer/lib/src/context/context.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.src.context.context;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
+import 'package:analyzer/plugin/resolver_provider.dart';
 import 'package:analyzer/plugin/task.dart';
 import 'package:analyzer/source/embedder.dart';
 import 'package:analyzer/src/cancelable_future.dart';
 import 'package:analyzer/src/context/cache.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/dart/element/type.dart';
 import 'package:analyzer/src/generated/constant.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/error.dart';
 import 'package:analyzer/src/generated/incremental_resolver.dart';
@@ skipping 194 matching lines @@
    * resolved.
    */
   Source incrementalResolutionValidation_lastLibrarySource;
 
   /**
    * The result of incremental resolution result of
    * [incrementalResolutionValidation_lastUnitSource].
    */
   CompilationUnit incrementalResolutionValidation_lastUnit;
 
+  @override
+  ResolverProvider fileResolverProvider;
+
   /**
    * Initialize a newly created analysis context.
    */
   AnalysisContextImpl() {
     _privatePartition = new UniversalCachePartition(this);
     _cache = createCacheFromSourceFactory(null);
     _taskManager = AnalysisEngine.instance.taskManager;
     for (WorkManagerFactory factory
         in AnalysisEngine.instance.enginePlugin.workManagerFactories) {
       WorkManager workManager = factory(this);
@@ skipping 1990 matching lines @@
     }
     DartSdk sdk = factory.dartSdk;
     if (sdk == null) {
       throw new IllegalArgumentException(
           "The source factory for an SDK analysis context must have a DartUriResolver");
     }
     return new AnalysisCache(
         <CachePartition>[AnalysisEngine.instance.partitionManager.forSdk(sdk)]);
   }
 }