Use async/await in all analysis domain tests.

pkg/analysis_server/test/analysis/notification_errors_test.dart

Index: pkg/analysis_server/test/analysis/notification_errors_test.dart
diff --git a/pkg/analysis_server/test/analysis/notification_errors_test.dart b/pkg/analysis_server/test/analysis/notification_errors_test.dart
index 46de68d6383ff0d164bac30744a24cbebb28eaeb..dbbe7af1dc99b1f211bc38bdf5560327ab3704b2 100644
--- a/pkg/analysis_server/test/analysis/notification_errors_test.dart
+++ b/pkg/analysis_server/test/analysis/notification_errors_test.dart
@@ -48,25 +48,24 @@ class NotificationErrorsTest extends AbstractAnalysisTest {
     super.tearDown();
   }
 
-  test_importError() {
+  test_importError() async {
     createProject();
 
     addTestFile('''
 import 'does_not_exist.dart';
 ''');
-    return waitForTasksFinished().then((_) {
-      List<AnalysisError> errors = filesErrors[testFile];
-      // Verify that we are generating only 1 error for the bad URI.
-      // https://github.com/dart-lang/sdk/issues/23754
-      expect(errors, hasLength(1));
-      AnalysisError error = errors[0];
-      expect(error.severity, AnalysisErrorSeverity.ERROR);
-      expect(error.type, AnalysisErrorType.COMPILE_TIME_ERROR);
-      expect(error.message, startsWith('Target of URI does not exist'));
-    });
+    await waitForTasksFinished();
+    List<AnalysisError> errors = filesErrors[testFile];
+    // Verify that we are generating only 1 error for the bad URI.
+    // https://github.com/dart-lang/sdk/issues/23754
+    expect(errors, hasLength(1));
+    AnalysisError error = errors[0];
+    expect(error.severity, AnalysisErrorSeverity.ERROR);
+    expect(error.type, AnalysisErrorType.COMPILE_TIME_ERROR);
+    expect(error.message, startsWith('Target of URI does not exist'));
   }
 
-  test_lintError() {
+  test_lintError() async {
     // Requires task model.
     AnalysisEngine.instance.useTaskModel = true;
 
@@ -86,69 +85,64 @@ linter:
         new AnalysisSetAnalysisRootsParams([projectPath], []).toRequest('0');
     handleSuccessfulRequest(request);
 
-    return waitForTasksFinished().then((_) {
-      AnalysisContext testContext = server.getContainingContext(testFile);
-      List<Linter> lints = getLints(testContext);
-      // Registry should only contain single lint rule.
-      expect(lints, hasLength(1));
-      LintRule lint = lints.first as LintRule;
-      expect(lint.name, camelCaseTypesLintName);
-      // Verify lint error result.
-      List<AnalysisError> errors = filesErrors[testFile];
-      expect(errors, hasLength(1));
-      AnalysisError error = errors[0];
-      expect(error.location.file, '/project/bin/test.dart');
-      expect(error.severity, AnalysisErrorSeverity.INFO);
-      expect(error.type, AnalysisErrorType.LINT);
-      expect(error.message, lint.description);
-    });
+    await waitForTasksFinished();
+    AnalysisContext testContext = server.getContainingContext(testFile);
+    List<Linter> lints = getLints(testContext);
+    // Registry should only contain single lint rule.
+    expect(lints, hasLength(1));
+    LintRule lint = lints.first as LintRule;
+    expect(lint.name, camelCaseTypesLintName);
+    // Verify lint error result.
+    List<AnalysisError> errors = filesErrors[testFile];
+    expect(errors, hasLength(1));
+    AnalysisError error = errors[0];
+    expect(error.location.file, '/project/bin/test.dart');
+    expect(error.severity, AnalysisErrorSeverity.INFO);
+    expect(error.type, AnalysisErrorType.LINT);
+    expect(error.message, lint.description);
   }
 
-  test_notInAnalysisRoot() {
+  test_notInAnalysisRoot() async {
     createProject();
     String otherFile = '/other.dart';
     addFile(otherFile, 'UnknownType V;');
     addTestFile('''
 import '/other.dart';
-
 main() {
   print(V);
 }
 ''');
-    return waitForTasksFinished().then((_) {
-      expect(filesErrors[otherFile], isNull);
-    });
+    await waitForTasksFinished();
+    expect(filesErrors[otherFile], isNull);
   }
 
-  test_ParserError() {
+  test_ParserError() async {
     createProject();
     addTestFile('library lib');
-    return waitForTasksFinished().then((_) {
-      List<AnalysisError> errors = filesErrors[testFile];
-      expect(errors, hasLength(1));
-      AnalysisError error = errors[0];
-      expect(error.location.file, '/project/bin/test.dart');
-      expect(error.location.offset, isPositive);
-      expect(error.location.length, isNonNegative);
-      expect(error.severity, AnalysisErrorSeverity.ERROR);
-      expect(error.type, AnalysisErrorType.SYNTACTIC_ERROR);
-      expect(error.message, isNotNull);
-    });
+    await waitForTasksFinished();
+    List<AnalysisError> errors = filesErrors[testFile];
+    expect(errors, hasLength(1));
+    AnalysisError error = errors[0];
+    expect(error.location.file, '/project/bin/test.dart');
+    expect(error.location.offset, isPositive);
+    expect(error.location.length, isNonNegative);
+    expect(error.severity, AnalysisErrorSeverity.ERROR);
+    expect(error.type, AnalysisErrorType.SYNTACTIC_ERROR);
+    expect(error.message, isNotNull);
   }
 
-  test_StaticWarning() {
+  test_StaticWarning() async {
     createProject();
     addTestFile('''
 main() {
   print(UNKNOWN);
 }
 ''');
-    return waitForTasksFinished().then((_) {
-      List<AnalysisError> errors = filesErrors[testFile];
-      expect(errors, hasLength(1));
-      AnalysisError error = errors[0];
-      expect(error.severity, AnalysisErrorSeverity.WARNING);
-      expect(error.type, AnalysisErrorType.STATIC_WARNING);
-    });
+    await waitForTasksFinished();
+    List<AnalysisError> errors = filesErrors[testFile];
+    expect(errors, hasLength(1));
+    AnalysisError error = errors[0];
+    expect(error.severity, AnalysisErrorSeverity.WARNING);
+    expect(error.type, AnalysisErrorType.STATIC_WARNING);
   }
 }