Relax a null check in context_manager.dart.

pkg/analysis_server/lib/src/context_manager.dart

Index: pkg/analysis_server/lib/src/context_manager.dart
diff --git a/pkg/analysis_server/lib/src/context_manager.dart b/pkg/analysis_server/lib/src/context_manager.dart
index e7460a9412159c7d8cf6055fa964ce14e23ceaa6..9baa103efdbff485a52b6c5f2912d55087b96ae4 100644
--- a/pkg/analysis_server/lib/src/context_manager.dart
+++ b/pkg/analysis_server/lib/src/context_manager.dart
@@ -1044,7 +1044,7 @@ class ContextManagerImpl implements ContextManager {
       ContextBuilder builder =
           callbacks.createContextBuilder(info.folder, defaultContextOptions);
       AnalysisOptions options = builder.getAnalysisOptions(contextRoot,
-          contextRoot: info?.analysisDriver?.contextRoot);
+          contextRoot: info.analysisDriver?.contextRoot);
       SourceFactory factory = builder.createSourceFactory(contextRoot, options);
       if (enableNewAnalysisDriver) {
         AnalysisDriver driver = info.analysisDriver;