Keep the 'fetching files' message until the Drive root is ready to be read.

chrome/browser/resources/file_manager/js/volume_manager.js

Index: chrome/browser/resources/file_manager/js/volume_manager.js
diff --git a/chrome/browser/resources/file_manager/js/volume_manager.js b/chrome/browser/resources/file_manager/js/volume_manager.js
index 73237b972c6575072608f4401878f17ddf33b52f..a9237804fe057ff8e8eff1a181748acd0f4111a8 100644
--- a/chrome/browser/resources/file_manager/js/volume_manager.js
+++ b/chrome/browser/resources/file_manager/js/volume_manager.js
@@ -253,7 +253,14 @@ VolumeManager.prototype.onMountCompleted_ = function(event) {
 VolumeManager.prototype.waitDriveLoaded_ = function(mountPath, callback) {
   chrome.fileBrowserPrivate.requestLocalFileSystem(function(filesystem) {
     filesystem.root.getDirectory(mountPath, {},
-        callback.bind(null, true),
+        function(entry) {
+            // After introducion of the 'fast-fetch' feature, getting the root
+            // entry does not start fetching data. Rather, it starts when the
+            // entry is read.
+            entry.createReader().readEntries(
+                callback.bind(null, true),
+                callback.bind(null, false));
+        },
         callback.bind(null, false));
   });
 };