Revert "Fix observatory tests broken by running dartfmt."

runtime/observatory/tests/observatory_ui/stack_trace_tree_config/element_test.dart

Index: runtime/observatory/tests/observatory_ui/stack_trace_tree_config/element_test.dart
diff --git a/runtime/observatory/tests/observatory_ui/stack_trace_tree_config/element_test.dart b/runtime/observatory/tests/observatory_ui/stack_trace_tree_config/element_test.dart
index 1a8bef14a2941a92849ef1903035e40fa3387003..f8c0f0004e56c91094b998a0b8f2664fad207210 100644
--- a/runtime/observatory/tests/observatory_ui/stack_trace_tree_config/element_test.dart
+++ b/runtime/observatory/tests/observatory_ui/stack_trace_tree_config/element_test.dart
@@ -142,10 +142,10 @@ main() {
         expect(e.mode, equals(ProfileTreeMode.code));
       }, count: 1));
       final select = (e.querySelector('.mode-select') as SelectElement);
-      select.selectedIndex = select.options.indexOf((select.options.toSet()
-            ..removeAll(select.selectedOptions))
-          .toList()
-          .first);
+      select.selectedIndex = select.options.indexOf(
+          (select.options.toSet()
+            ..removeAll(select.selectedOptions)).toList().first
+        );
       select.dispatchEvent(new Event("change"));
       e.remove();
       await e.onRendered.first;
@@ -159,10 +159,10 @@ main() {
         expect(e.direction, equals(M.ProfileTreeDirection.inclusive));
       }, count: 1));
       final select = (e.querySelector('.direction-select') as SelectElement);
-      select.selectedIndex = select.options.indexOf((select.options.toSet()
-            ..removeAll(select.selectedOptions))
-          .toList()
-          .first);
+      select.selectedIndex = select.options.indexOf(
+          (select.options.toSet()
+            ..removeAll(select.selectedOptions)).toList().first
+        );
       select.dispatchEvent(new Event("change"));
       e.remove();
       await e.onRendered.first;