Reland r202508: Made the open menu item in the context menu updated when the context menu is open.

Original patch broke SelectFileAndOpen browser test. This is because Files.app
notify 'selection-change-complete' to the tests even if the selection is empty.
This CL is fixed the problem by adding a check of the number of selected items.

Previously reverted CL: crrev.com/15950003

BUG=243687
TEST=browser_tests

Review URL: https://chromiumcodereview.appspot.com/15808007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@202798 0039d316-1c4b-4281-b951-d872f2087c98

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

@@ -476,80 +476,74 @@ FileSelectionHandler.prototype.updateFileSelectionAsync = function(selection) {
   if (this.selection != selection) return;
 
   // Update the file tasks.
-  var onTasks = function() {
-    if (this.selection != selection) return;
-    selection.tasks.display(this.taskItems_);
-    selection.tasks.updateMenuItem();
-  }.bind(this);
-
   if (this.fileManager_.dialogType == DialogType.FULL_PAGE &&
       selection.directoryCount == 0 && selection.fileCount > 0) {
-    selection.createTasks(onTasks);
+    selection.createTasks(function() {
+      if (this.selection != selection)
+        return;
+      selection.tasks.display(this.taskItems_);
+      selection.tasks.updateMenuItem();
+    }.bind(this));
   } else {
     this.taskItems_.hidden = true;
   }
 
-  // Update the UI.
+  // Update preview panels.
   var wasVisible = this.isPreviewPanelVisibile_();
+  var thumbnailEntries;
+  if (util.platform.newUI() && selection.totalCount == 0) {
+    thumbnailEntries = [
+      this.fileManager_.getCurrentDirectoryEntry()
+    ];
+  } else {
+    thumbnailEntries = selection.entries;
+    if (selection.totalCount != 1) {
+      selection.computeBytes(function() {
+        if (this.selection != selection)
+          return;
+        this.updatePreviewPanelText_();
+      }.bind(this));
+    }
+  }
   this.updatePreviewPanelVisibility_();
+  this.updatePreviewPanelText_();
+  this.showPreviewThumbnails_(thumbnailEntries);
 
-  if (util.platform.newUI() && selection.totalCount == 0) {
+  // Update breadcrums.
+  var updateTarget = null;
+  if (util.platform.newUI()) {
     var path = this.fileManager_.getCurrentDirectory();
-    // Hides the breadcrumbs list on the root path.
-    if (PathUtil.isRootPath(path))
-      this.updatePreviewPanelBreadcrumbs_(null);
-    else
-      this.updatePreviewPanelBreadcrumbs_(path);
-    var entry = this.fileManager_.getCurrentDirectoryEntry();
-    this.showPreviewThumbnails_([entry]);
-    this.updatePreviewPanelText_();
-    return;
+    if (selection.totalCount == 1) {
+      // Shows the breadcrumb list when a file is selected.
+      updateTarget = selection.entries[0].fullPath;
+    } else if (selection.totalCount == 0 && !PathUtil.isRootPath(path)) {
+      // Shows the breadcrumb list when no file is selected and the current
+      // directory is non-root path.
+      updateTarget = path;
+    }
   }
+  this.updatePreviewPanelBreadcrumbs_(updateTarget);
 
-  this.fileManager_.updateContextMenuActionItems(null, false);
+  // Scroll to item
   if (!wasVisible && this.selection.totalCount == 1) {
     var list = this.fileManager_.getCurrentList();
     list.scrollIndexIntoView(list.selectionModel.selectedIndex);
   }
 
   // Sync the commands availability.
-  var commands = this.fileManager_.dialogDom_.querySelectorAll('command');
-  for (var i = 0; i < commands.length; i++)
-    commands[i].canExecuteChange();
-
-  if (!util.platform.newUI()) {
-    this.updateSearchBreadcrumbs_();
-    // Update the summary information.
-    var onBytes = function() {
-      if (this.selection != selection) return;
-      this.updatePreviewPanelText_();
-    }.bind(this);
-    selection.computeBytes(onBytes);
-    this.updatePreviewPanelText_();
-  } else {
-    if (selection.totalCount == 1) {
-      // Shows the breadcrumb list.
-      var firstEntry = selection.entries[0];
-      this.updatePreviewPanelBreadcrumbs_(firstEntry.fullPath);
-      this.updatePreviewPanelText_();
-    } else {
-      this.updatePreviewPanelBreadcrumbs_(null);
-
-      // Update the summary information.
-      var onBytes = function() {
-        if (this.selection != selection) return;
-        this.updatePreviewPanelText_();
-      }.bind(this);
-      selection.computeBytes(onBytes);
-      this.updatePreviewPanelText_();
-    }
+  if (selection.totalCount != 0) {
+    var commands = this.fileManager_.dialogDom_.querySelectorAll('command');
+    for (var i = 0; i < commands.length; i++)
+      commands[i].canExecuteChange();
   }
 
-  // Inform tests it's OK to click buttons now.
-  chrome.test.sendMessage('selection-change-complete');
+  // Update context menu.
+  this.fileManager_.updateContextMenuActionItems(null, false);
 
-  // Show thumbnails.
-  this.showPreviewThumbnails_(selection.entries);
+  // Inform tests it's OK to click buttons now.
+  if (selection.totalCount > 0) {
+    chrome.test.sendMessage('selection-change-complete');
+  }
 };
 
 /**