convert completion tests to use new analysis driver

pkg/analysis_server/test/services/completion/dart/combinator_contributor_test.dart

Index: pkg/analysis_server/test/services/completion/dart/combinator_contributor_test.dart
diff --git a/pkg/analysis_server/test/services/completion/dart/combinator_contributor_test.dart b/pkg/analysis_server/test/services/completion/dart/combinator_contributor_test.dart
index 8b1349a6f250c0e501a6b0c69265ec31bd419180..4326f0eeda6b70f72f7ab1738e7377b178a6f8b5 100644
--- a/pkg/analysis_server/test/services/completion/dart/combinator_contributor_test.dart
+++ b/pkg/analysis_server/test/services/completion/dart/combinator_contributor_test.dart
@@ -61,11 +61,6 @@ class CombinatorContributorTest extends DartCompletionContributorTest {
       import "/testCD.dart";
       class X {}''');
 
-    // Assume that imported libraries have been resolved
-    if (!enableNewAnalysisDriver) {
-      context.resolveCompilationUnit2(importedLibSource, importedLibSource);
-    }
-
     await computeSuggestions();
     assertSuggestClass('A',
         relevance: DART_RELEVANCE_DEFAULT,
@@ -115,11 +110,6 @@ class CombinatorContributorTest extends DartCompletionContributorTest {
       import "/testCD.dart";
       class X {}''');
 
-    // Assume that imported libraries have been resolved
-    if (!enableNewAnalysisDriver) {
-      context.resolveCompilationUnit2(importedLibSource, importedLibSource);
-    }
-
     await computeSuggestions();
     assertSuggestClass('A',
         relevance: DART_RELEVANCE_DEFAULT,