test-infra: refactored new summary results into base ResultsFormatter class

This allows more specialized formatters to still reuse the results
summarization display from the base class.

llvm-svn: 255676
diff --git a/lldb/packages/Python/lldbsuite/test/dotest.py b/lldb/packages/Python/lldbsuite/test/dotest.py
index 536aced..9fc6894 100644
--- a/lldb/packages/Python/lldbsuite/test/dotest.py
+++ b/lldb/packages/Python/lldbsuite/test/dotest.py
@@ -383,7 +383,7 @@
     # and we're not a test inferior.
     if not args.inferior and configuration.results_formatter_name is None:
         configuration.results_formatter_name = (
-            "lldbsuite.test.basic_results_formatter.BasicResultsFormatter")
+            "lldbsuite.test.result_formatter.ResultsFormatter")
 
     # rerun-related arguments
     configuration.rerun_all_issues = args.rerun_all_issues