Use mako template for HTML report.
diff --git a/tools/run_tests/run_interop_tests.py b/tools/run_tests/run_interop_tests.py
index 2634164..ee3cddd 100755
--- a/tools/run_tests/run_interop_tests.py
+++ b/tools/run_tests/run_interop_tests.py
@@ -686,9 +686,9 @@
   else:
     jobset.message('SUCCESS', 'All tests passed', do_newline=True)
 
-  report_utils.render_xml_report(resultset, 'report.xml')
+  report_utils.render_junit_xml_report(resultset, 'report.xml')
   
-  report_utils.render_html_report(
+  report_utils.render_interop_html_report(
       set([str(l) for l in languages]), servers, _TEST_CASES, _AUTH_TEST_CASES, 
       _HTTP2_TEST_CASES, resultset, num_failures,
       args.cloud_to_prod_auth or args.cloud_to_prod, args.http2_interop)