Add tests to vaildate the analysis server's integration test coverage.

pkg/analysis_server/test/integration/test_all.dart

Index: pkg/analysis_server/test/integration/test_all.dart
diff --git a/pkg/analysis_server/test/integration/test_all.dart b/pkg/analysis_server/test/integration/test_all.dart
index 5c954fe6fa4e7896e4ea3b0a60fff35f4430c7c6..8e0c603d4aef10362580574e06b278a6a696bfdb 100644
--- a/pkg/analysis_server/test/integration/test_all.dart
+++ b/pkg/analysis_server/test/integration/test_all.dart
@@ -8,6 +8,7 @@ import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 import 'analysis/test_all.dart' as analysis_test_all;
 import 'completion/test_all.dart' as completion_test_all;
+import 'coverage_test.dart' as coverage_test;
 import 'execution/test_all.dart' as execution_test_all;
 import 'search/test_all.dart' as search_test_all;
 import 'server/test_all.dart' as server_test_all;
@@ -22,5 +23,7 @@ main() {
     execution_test_all.main();
     search_test_all.main();
     server_test_all.main();
+
+    coverage_test.main();
   }, name: 'analysis_server_integration');
 }