Support for excluded files/folders.

pkg/analyzer/test/file_system/memory_file_system_test.dart

Index: pkg/analyzer/test/file_system/memory_file_system_test.dart
diff --git a/pkg/analyzer/test/file_system/memory_file_system_test.dart b/pkg/analyzer/test/file_system/memory_file_system_test.dart
index a91aa4b42fb918cf4823298318e635e6dec44d9e..2a7b669b5e74b90a1c459f19e87682cdb2288b09 100644
--- a/pkg/analyzer/test/file_system/memory_file_system_test.dart
+++ b/pkg/analyzer/test/file_system/memory_file_system_test.dart
@@ -260,6 +260,13 @@ main() {
         expect(file1.hashCode, equals(file2.hashCode));
       });
 
+      test('isOrContains', () {
+        String path = '/foo/bar/file.txt';
+        File file = provider.getResource(path);
+        expect(file.isOrContains(path), isTrue);
+        expect(file.isOrContains('/foo/bar'), isFalse);
+      });
+
       test('shortName', () {
         File file = provider.getResource('/foo/bar/file.txt');
         expect(file.shortName, 'file.txt');
@@ -310,6 +317,13 @@ main() {
         expect(folder.contains('/foo/bar'), isFalse);
       });
 
+      test('isOrContains', () {
+        expect(folder.isOrContains('/foo/bar'), isTrue);
+        expect(folder.isOrContains('/foo/bar/aaa.txt'), isTrue);
+        expect(folder.isOrContains('/foo/bar/aaa/bbb.txt'), isTrue);
+        expect(folder.isOrContains('/baz.txt'), isFalse);
+      });
+
       group('getChild', () {
         test('does not exist', () {
           File file = folder.getChild('file.txt');