Switch the default from non-driver to driver in several tests

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

Index: pkg/analysis_server/test/services/completion/dart/uri_contributor_test.dart
diff --git a/pkg/analysis_server/test/services/completion/dart/uri_contributor_test.dart b/pkg/analysis_server/test/services/completion/dart/uri_contributor_test.dart
index cfed83c955ed0855d304c86ae8820ab060e0d453..d35e327a5960dc41d495ae129336b8752db3db60 100644
--- a/pkg/analysis_server/test/services/completion/dart/uri_contributor_test.dart
+++ b/pkg/analysis_server/test/services/completion/dart/uri_contributor_test.dart
@@ -22,9 +22,6 @@ main() {
 @reflectiveTest
 class UriContributorTest extends DartCompletionContributorTest {
   @override
-  bool get enableNewAnalysisDriver => true;
-
-  @override
   DartCompletionContributor createContributor() {
     return new UriContributor();
   }
@@ -466,9 +463,6 @@ class UriContributorTest extends DartCompletionContributorTest {
 @reflectiveTest
 class UriContributorWindowsTest extends DartCompletionContributorTest {
   @override
-  bool get enableNewAnalysisDriver => true;
-
-  @override
   DartCompletionContributor createContributor() {
     return new UriContributor();
   }