drive: Remove FileCacheObserver::OnCacheCommitted

chrome/browser/chromeos/drive/file_system/update_operation_unittest.cc

Index: chrome/browser/chromeos/drive/file_system/update_operation_unittest.cc
diff --git a/chrome/browser/chromeos/drive/file_system/update_operation_unittest.cc b/chrome/browser/chromeos/drive/file_system/update_operation_unittest.cc
index 951a2a561d2bbb7a29a7ebb42db5124309e98705..a2ad16dacfd27c3da2a716a266eb7ca67a5f0a5d 100644
--- a/chrome/browser/chromeos/drive/file_system/update_operation_unittest.cc
+++ b/chrome/browser/chromeos/drive/file_system/update_operation_unittest.cc
@@ -67,14 +67,6 @@ TEST_F(UpdateOperationTest, UpdateFileByResourceId_PersistentFile) {
   google_apis::test_util::RunBlockingPoolTask();
   EXPECT_EQ(FILE_ERROR_OK, error);
 
-  // Commit the dirty bit.
-  error = FILE_ERROR_FAILED;
-  cache()->CommitDirtyOnUIThread(
-      kResourceId, kMd5,
-      google_apis::test_util::CreateCopyResultCallback(&error));
-  google_apis::test_util::RunBlockingPoolTask();
-  EXPECT_EQ(FILE_ERROR_OK, error);
-
   int64 original_changestamp = fake_service()->largest_changestamp();
 
   // The callback will be called upon completion of