Fix file manager to better handle missing roots and scan failure

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

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Setting the src of an img to an empty string can crash the browser, so we
 // use an empty 1x1 gif instead.
 
 /**
  * FileManager constructor.
  *
@@ skipping 1134 matching lines @@
                (this.dialogType_ == FileManager.DialogType.SELECT_SAVEAS_FILE ||
                 this.dialogType_ == FileManager.DialogType.FULL_PAGE);
 
       case 'unmount':
         return true;
 
       case 'format':
         var entry =
             this.getRootEntry_(this.rootsList_.selectionModel.selectedIndex);
 
-        return DirectoryModel.getRootType(entry.fullPath) ==
+        return entry && DirectoryModel.getRootType(entry.fullPath) ==
                DirectoryModel.RootType.REMOVABLE;
     }
   };
 
   FileManager.prototype.getRootEntry_ = function(index) {
     if (index == -1)
       return null;
 
     return this.rootsList_.dataModel.item(index);
   };
@@ skipping 300 matching lines @@
 
   /**
    * Restores current directory and may be a selected item after page load (or
    * reload) or popping a state (after click on back/forward). If location.hash
    * is present it means that the user has navigated somewhere and that place
    * will be restored. defaultPath primarily is used with save/open dialogs.
    * Default path may also contain a file name. Freshly opened file manager
    * window has neither.
    */
   FileManager.prototype.setupCurrentDirectory_ = function() {
-    // Avoid a bunch of intermediate list redraws while the data model is
-    // cleared and updated.  Note that it may (or may not) be desirable to draw
-    // partial results as we get them, but today the DirectoryReader API
-    // generally returns all entries in one chunk so even without this batching
-    // we wouldn't have incremental updates.
-    this.table_.startBatchUpdates();
-    var onLoaded = this.table_.endBatchUpdates.bind(this.table_);
 
     if (location.hash) {
       // Location hash has the highest priority.
       var path = decodeURI(location.hash.substr(1));
 
       // In the FULL_PAGE mode if the path points to a file we should invoke
       // the default action after selecting it.
       if (this.dialogType_ == FileManager.DialogType.FULL_PAGE) {
         // To prevent the file list flickering for a moment before the action
         // is executed we hide it under a white div.
@@ skipping 13 matching lines @@
             removeShade();
             foundLeaf = false;
           }
         }
 
         // TODO(kaznacheev): refactor dispatchDefaultTask to accept an array
         // of urls instead of a selection. This will remove the need to wait
         // until the selection is done.
         var self = this;
         function onLoadedActivateLeaf() {
-          onLoaded();
           if (foundLeaf) {
             self.dispatchDefaultTask_();
             setTimeout(removeShade, 1000);
           }
         }
         this.directoryModel_.setupPath(path, onLoadedActivateLeaf, onResolve);
 
         return;
       }
 
-      this.directoryModel_.setupPath(path, onLoaded);
+      this.directoryModel_.setupPath(path);
       return;
     }
 
     if (this.params_.defaultPath) {
       var path = this.params_.defaultPath;
       if (this.dialogType_ == FileManager.DialogType.SELECT_SAVEAS_FILE) {
-        this.directoryModel_.setupPath(path, onLoaded,
+        this.directoryModel_.setupPath(path, undefined,
             function(basePath, leafName) {
               this.filenameInput_.value = leafName;
               this.selectDefaultPathInFilenameInput_();
             }.bind(this));
         return;
       }
 
-      this.directoryModel_.setupPath(path, onLoaded);
+      this.directoryModel_.setupPath(path);
       return;
     }
 
-    this.directoryModel_.setupDefaultPath(onLoaded);
+    this.directoryModel_.setupDefaultPath();
   };
 
   /**
    * Tweak the UI to become a particular kind of dialog, as determined by the
    * dialog type parameter passed to the constructor.
    */
   FileManager.prototype.initDialogType_ = function() {
     var defaultTitle;
     var okLabel = str('OPEN_LABEL');
 
@@ skipping 2592 matching lines @@
           });
       }, onError);
 
       function onError(err) {
         console.log('Error while checking free space: ' + err);
         setTimeout(doCheck, 1000 * 60);
       }
     }
   }
 })();