Temp fix to allow plugins to serve the getErrors APIs.

pkg/analysis_server/lib/src/domain_analysis.dart

Index: pkg/analysis_server/lib/src/domain_analysis.dart
diff --git a/pkg/analysis_server/lib/src/domain_analysis.dart b/pkg/analysis_server/lib/src/domain_analysis.dart
index c8f2ec280c939c6962990adb4a84aecdc0aaf023..894f30996fce3a8fd3effd5066eeb6912b317a63 100644
--- a/pkg/analysis_server/lib/src/domain_analysis.dart
+++ b/pkg/analysis_server/lib/src/domain_analysis.dart
@@ -67,6 +67,16 @@ class AnalysisDomainHandler implements RequestHandler {
 
     if (server.options.enableNewAnalysisDriver) {
       var result = await server.getAnalysisResult(file);
+
+      if (server.onResultErrorSupplementor != null) {
+        if (result != null) {
+          await server.onResultErrorSupplementor(file, result.errors);
+        } else {
+          server.onNoAnalysisResult(file, send);
+          return;
+        }
+      }
+
       send(result?.driver?.analysisOptions, result?.lineInfo, result?.errors);
       return;
     }