convert uri contributor to use new task model

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

Index: pkg/analysis_server/test/services/completion/dart/test_all.dart
diff --git a/pkg/analysis_server/test/services/completion/dart/test_all.dart b/pkg/analysis_server/test/services/completion/dart/test_all.dart
index 156ce7ade3178f7083481074db38d72bd75e8d4f..dffcb38eb27b5359b288c4d3ad2c0c91f769e915 100644
--- a/pkg/analysis_server/test/services/completion/dart/test_all.dart
+++ b/pkg/analysis_server/test/services/completion/dart/test_all.dart
@@ -11,6 +11,7 @@ import 'arglist_contributor_test.dart' as arglist_test;
 import 'common_usage_sorter_test.dart' as common_usage_test;
 import 'inherited_contributor_test.dart' as inherited_contributor_test;
 import 'keyword_contributor_test.dart' as keyword_test;
+import 'uri_contributor_test.dart' as uri_contributor_test;
 
 /// Utility for manually running all tests.
 main() {
@@ -20,5 +21,6 @@ main() {
     common_usage_test.main();
     inherited_contributor_test.main();
     keyword_test.main();
+    uri_contributor_test.main();
   });
 }