Validate cache consistency asynchronously. Compute modification times of physical files in a separa…

pkg/analyzer/test/file_system/physical_resource_provider_test.dart

Index: pkg/analyzer/test/file_system/physical_resource_provider_test.dart
diff --git a/pkg/analyzer/test/file_system/physical_resource_provider_test.dart b/pkg/analyzer/test/file_system/physical_resource_provider_test.dart
index 790eff7dcb11780f363573dc6ae0ee411bbe7c3f..939882283488e8295bb92ee53d7d47e09b347645 100644
--- a/pkg/analyzer/test/file_system/physical_resource_provider_test.dart
+++ b/pkg/analyzer/test/file_system/physical_resource_provider_test.dart
@@ -377,6 +377,15 @@ class FolderTest extends _BaseTest {
 
 @reflectiveTest
 class PhysicalResourceProviderTest extends _BaseTest {
+  test_getModificationTimes() async {
+    PhysicalResourceProvider provider = PhysicalResourceProvider.INSTANCE;
+    String path = join(tempPath, 'file1.txt');
+    new io.File(path).writeAsStringSync('');
+    Source source = provider.getFile(path).createSource();
+    List<int> times = await provider.getModificationTimes([source]);
+    expect(times, [source.modificationStamp]);
+  }
+
   void test_getStateLocation_uniqueness() {
     PhysicalResourceProvider provider = PhysicalResourceProvider.INSTANCE;
     String idOne = 'one';