Extract ElementBuilder tests into a separate file.

pkg/analyzer/test/dart/element/test_all.dart

Index: pkg/analyzer/test/dart/element/test_all.dart
diff --git a/pkg/analyzer/test/dart/element/test_all.dart b/pkg/analyzer/test/dart/element/test_all.dart
index bb4c7799ac9419424f7dec27aa07cbdb1aafef52..d0e4cea2ef264c66a15d0cfa6177507c9e161131 100644
--- a/pkg/analyzer/test/dart/element/test_all.dart
+++ b/pkg/analyzer/test/dart/element/test_all.dart
@@ -6,11 +6,13 @@ library analyzer.test.dart.element.test_all;
 
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
+import 'builder_test.dart' as builder;
 import 'element_test.dart' as element;
 
 /// Utility for manually running all tests.
 main() {
   defineReflectiveSuite(() {
+    builder.main();
     element.main();
   }, name: 'element');
 }