Postpone connecting to GData even more, provide progress indication.

chrome/browser/resources/file_manager/js/directory_model.js

Index: chrome/browser/resources/file_manager/js/directory_model.js
diff --git a/chrome/browser/resources/file_manager/js/directory_model.js b/chrome/browser/resources/file_manager/js/directory_model.js
index aa3bfecebb92f75de2ea8dd23d76203f49e3dd23..24852b60bd3184075269c8b0f3098f2f705771bf 100644
--- a/chrome/browser/resources/file_manager/js/directory_model.js
+++ b/chrome/browser/resources/file_manager/js/directory_model.js
@@ -754,10 +754,11 @@ DirectoryModel.prototype = {
   },
 
   /**
-   * Get root entries asynchronously. Invokes callback
-   * when have finished.
+   * Get root entries asynchronously.
+   * @param {function(Array.<Entry>} callback Called when roots are resolved.
+   * @param {boolean} resolveGData See comment for updateRoots.
    */
-  resolveRoots_: function(callback) {
+  resolveRoots_: function(callback, resolveGData) {
     var groups = {
       downloads: null,
       archives: null,
@@ -807,6 +808,8 @@ DirectoryModel.prototype = {
       console.log('onGDataError');
       console.log(error);
       self.unmountedGDataEntry_ = {
+        unmounted: true,  // Clients use this field to distinguish a fake root.
+        toURL: function() { return '' },
         fullPath: '/' + DirectoryModel.GDATA_DIRECTORY
       };
       groups.gdata = [self.unmountedGDataEntry_];
@@ -821,14 +824,23 @@ DirectoryModel.prototype = {
     util.readDirectory(root, DirectoryModel.REMOVABLE_DIRECTORY,
                        append.bind(this, 'removables'));
     if (this.showGData_) {
-      root.getDirectory(DirectoryModel.GDATA_DIRECTORY, { create: false },
-                        onGData, onGDataError);
+      if (resolveGData) {
+        root.getDirectory(DirectoryModel.GDATA_DIRECTORY, { create: false },
+                          onGData, onGDataError);
+      } else {
+        onGDataError('lazy mount');
+      }
     } else {
       groups.gdata = [];
     }
   },
 
-  updateRoots: function(opt_callback) {
+  /**
+  * @param {function} opt_callback Called when all roots are resolved.
+  * @param {boolean} opt_resolveGData If true GData should be resolved for real,
+  *                                   If false a stub entry should be created.
+  */
+  updateRoots: function(opt_callback, opt_resolveGData) {
     console.log('directoryModel_.updateRoots');
     var self = this;
     this.resolveRoots_(function(rootEntries) {
@@ -842,7 +854,7 @@ DirectoryModel.prototype = {
 
       if (opt_callback)
         opt_callback();
-    });
+    }, opt_resolveGData);
   },
 
   onRootsSelectionChanged_: function(event) {