Split out options from ContextBuilder

pkg/analyzer/tool/task_dependency_graph/generate.dart

Index: pkg/analyzer/tool/task_dependency_graph/generate.dart
diff --git a/pkg/analyzer/tool/task_dependency_graph/generate.dart b/pkg/analyzer/tool/task_dependency_graph/generate.dart
index 9761e90d0675c02a1593398b02afbb0bd2b0b05c..26745f6fdb8cf43455b0d8c36259fcf7f67fbd06 100644
--- a/pkg/analyzer/tool/task_dependency_graph/generate.dart
+++ b/pkg/analyzer/tool/task_dependency_graph/generate.dart
@@ -154,17 +154,19 @@ ${generateGraphData()}
     DartSdk sdk = new FolderBasedDartSdk(resourceProvider,
         FolderBasedDartSdk.defaultSdkDirectory(resourceProvider));
     context = AnalysisEngine.instance.createAnalysisContext();
-    ContextBuilder builder = new ContextBuilder(resourceProvider, null, null);
+    ContextBuilderOptions builderOptions = new ContextBuilderOptions();
     if (Platform.packageRoot != null) {
-      builder.defaultPackagesDirectoryPath =
-        Uri.parse(Platform.packageRoot).toFilePath();
+      builderOptions.defaultPackagesDirectoryPath =
+          Uri.parse(Platform.packageRoot).toFilePath();
     } else if (Platform.packageConfig != null) {
-      builder.defaultPackageFilePath =
-        Uri.parse(Platform.packageConfig).toFilePath();
+      builderOptions.defaultPackageFilePath =
+          Uri.parse(Platform.packageConfig).toFilePath();
     } else {
       // Let the context builder use the default algorithm for package
       // resolution.
     }
+    ContextBuilder builder = new ContextBuilder(resourceProvider, null, null,
+        options: builderOptions);
     List<UriResolver> uriResolvers = [
       new DartUriResolver(sdk),
       new PackageMapUriResolver(resourceProvider,