CrOS FilesApp integrate with crostini

* New fileManagerPrivate APIs:
 - isCrostiniEnabled: returns true if device supports crostini
   and termina/penguin container exists.  This function is
   controlled by flag 'crostini-files'.
 - mountCrostiniContainer: starts and mounts container.

* Created new root type NavigationModelSFTPMountItem which uses
  a FakeEntry, similar to 'Recent', to show the 'Linux Files' root.

* Click handler for Linux Files will start and mount crostini container.

* Code in NavigationModel to order roots detects when mounted
  volumes already contains an FSP-provided mount for
  fileSystemId='crostini'.  In this case, the fake root is left out
  and the real volume should be in the same position.

* Error handling code for SFTP mount/disconnect to be implemented
  when sshfs is available.

Bug: 834103
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I8a3bec948871dc9671ea513d7378035d89d565eb
Reviewed-on: https://chromium-review.googlesource.com/1025545
Commit-Queue: Joel Hockey <joelhockey@chromium.org>
Reviewed-by: Sasha Morrissey <sashab@chromium.org>
Reviewed-by: Naoki Fukino <fukino@chromium.org>
Reviewed-by: Mark Pearson <mpearson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#557104}

chrome/app/chromeos_strings.grdp

@@ -215,6 +215,9 @@
   <message name="IDS_FILE_BROWSER_DOWNLOADS_DIRECTORY_LABEL" desc="Downloads local directory label.">
     Downloads
   </message>
+  <message name="IDS_FILE_BROWSER_LINUX_FILES_ROOT_LABEL" desc="A label for the 'Linux Files' root which shows crostini files.">
+    Linux Files
+  </message>
   <message name="IDS_FILE_BROWSER_MEDIA_VIEW_IMAGES_ROOT_LABEL" desc="A label for the 'Images' root of media views.">
     Images
   </message>

chrome/browser/chromeos/extensions/file_manager/private_api_misc.cc

@@ -11,11 +11,13 @@
 #include <utility>
 #include <vector>
 
+#include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/browser_process.h"
+#include "chrome/browser/chromeos/crostini/crostini_manager.h"
 #include "chrome/browser/chromeos/drive/file_system_util.h"
 #include "chrome/browser/chromeos/extensions/file_manager/private_api_util.h"
 #include "chrome/browser/chromeos/file_manager/fileapi_util.h"
@@ -41,6 +43,7 @@
 #include "chrome/common/extensions/api/manifest_types.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/services/file_util/public/cpp/zip_file_creator.h"
+#include "chromeos/chromeos_switches.h"
 #include "chromeos/settings/timezone_settings.h"
 #include "components/account_id/account_id.h"
 #include "components/drive/drive_pref_names.h"
@@ -640,6 +643,25 @@ void FileManagerPrivateConfigureVolumeFunction::OnCompleted(
   Respond(NoArguments());
 }
 
+bool IsCrostiniEnabled() {
+  return base::CommandLine::ForCurrentProcess()->HasSwitch(
+             chromeos::switches::kCrostiniFiles) &&
+         crostini::CrostiniManager::IsCrosTerminaInstalled();
+}
+
+ExtensionFunction::ResponseAction
+FileManagerPrivateIsCrostiniEnabledFunction::Run() {
+  return RespondNow(
+      OneArgument(std::make_unique<base::Value>(IsCrostiniEnabled())));
+}
+
+ExtensionFunction::ResponseAction
+FileManagerPrivateMountCrostiniContainerFunction::Run() {
+  // TOOD(https://crbug.com/832509): implement MountCrostiniContainer.
+  DCHECK(IsCrostiniEnabled());
+  return RespondNow(NoArguments());
+}
+
 FileManagerPrivateInternalGetCustomActionsFunction::
     FileManagerPrivateInternalGetCustomActionsFunction()
     : chrome_details_(this) {}

chrome/browser/chromeos/extensions/file_manager/private_api_misc.h

@@ -261,6 +261,34 @@ class FileManagerPrivateConfigureVolumeFunction
   DISALLOW_COPY_AND_ASSIGN(FileManagerPrivateConfigureVolumeFunction);
 };
 
+// Implements the chrome.fileManagerPrivate.isCrostiniEnabled method.
+// Gets crostini sftp mount params.
+class FileManagerPrivateIsCrostiniEnabledFunction
+    : public UIThreadExtensionFunction {
+ public:
+  DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.isCrostiniEnabled",
+                             FILEMANAGERPRIVATE_ISCROSTINIENABLED)
+
+ protected:
+  ~FileManagerPrivateIsCrostiniEnabledFunction() override {}
+
+  ResponseAction Run() override;
+};
+
+// Implements the chrome.fileManagerPrivate.mountCrostiniContainer method.
+// Starts and mounts crostini container.
+class FileManagerPrivateMountCrostiniContainerFunction
+    : public UIThreadExtensionFunction {
+ public:
+  DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.mountCrostiniContainer",
+                             FILEMANAGERPRIVATE_MOUNTCROSTINICONTAINER)
+
+ protected:
+  ~FileManagerPrivateMountCrostiniContainerFunction() override {}
+
+  ResponseAction Run() override;
+};
+
 // Implements the chrome.fileManagerPrivate.getCustomActions method.
 class FileManagerPrivateInternalGetCustomActionsFunction
     : public UIThreadExtensionFunction {

chrome/browser/chromeos/extensions/file_manager/private_api_strings.cc

@@ -724,6 +724,7 @@ ExtensionFunction::ResponseAction FileManagerPrivateGetStringsFunction::Run() {
   SET_STRING("TOTAL_FILE_COUNT", IDS_FILE_BROWSER_TOTAL_FILE_COUNT_LABEL);
   SET_STRING("IMAGE_RESOLUTION_COLUMN_LABEL",
              IDS_FILE_BROWSER_IMAGE_RESOLUTION_COLUMN_LABEL);
+  SET_STRING("LINUX_FILES_ROOT_LABEL", IDS_FILE_BROWSER_LINUX_FILES_ROOT_LABEL);
   SET_STRING("MEDIA_ARTIST_COLUMN_LABEL",
              IDS_FILE_BROWSER_MEDIA_ARTIST_COLUMN_LABEL);
   SET_STRING("MEDIA_TITLE_COLUMN_LABEL",

chrome/common/extensions/api/file_manager_private.idl

@@ -1072,6 +1072,13 @@ interface Functions {
   [nocompile]
   static void getRecentFiles(SourceRestriction restriction,
                              GetRecentFilesCallback callback);
+
+  // Returns true if crostini is enabled.
+  // |callback|
+  static void isCrostiniEnabled(BooleanCallback callback);
+
+  // Starts and mounts crostini container.
+  static void mountCrostiniContainer();
 };
 
 interface Events {

extensions/browser/extension_function_histogram_value.h

@@ -1310,6 +1310,8 @@ enum HistogramValue {
   WALLPAPERPRIVATE_GETCURRENTWALLPAPERTHUMBNAIL,
   ACCESSIBILITY_PRIVATE_ONSELECTTOSPEAKSTATECHANGED,
   INPUTMETHODPRIVATE_GETCOMPOSITIONBOUNDS,
+  FILEMANAGERPRIVATE_ISCROSTINIENABLED,
+  FILEMANAGERPRIVATE_MOUNTCROSTINICONTAINER,
   // Last entry: Add new entries above, then run:
   // python tools/metrics/histograms/update_extension_histograms.py
   ENUM_BOUNDARY

third_party/closure_compiler/externs/file_manager_private.js

@@ -728,6 +728,17 @@ chrome.fileManagerPrivate.getRecentFiles = function(restriction, callback) {};
 chrome.fileManagerPrivate.executeCustomAction = function(
     entries, actionId, callback) {};
 
+/**
+ * Returns true if crostini is enabled.
+ * @param {function(!boolean)} callback
+ */
+chrome.fileManagerPrivate.isCrostiniEnabled = function(callback) {};
+
+/**
+ * Starts and mounts crostini container.
+ */
+chrome.fileManagerPrivate.mountCrostiniContainer = function() {};
+
 /** @type {!ChromeEvent} */
 chrome.fileManagerPrivate.onMountCompleted;
 

tools/metrics/histograms/enums.xml

@@ -15400,6 +15400,8 @@ Called by update_net_error_codes.py.-->
   <int value="1247" label="WALLPAPERPRIVATE_GETCURRENTWALLPAPERTHUMBNAIL"/>
   <int value="1248" label="ACCESSIBILITY_PRIVATE_ONSELECTTOSPEAKSTATECHANGED"/>
   <int value="1249" label="INPUTMETHODPRIVATE_GETCOMPOSITIONBOUNDS"/>
+  <int value="1250" label="FILEMANAGERPRIVATE_ISCROSTINIENABLED"/>
+  <int value="1251" label="FILEMANAGERPRIVATE_MOUNTCROSTINICONTAINER"/>
 </enum>
 
 <enum name="ExtensionIconState">

ui/file_manager/file_manager/background/js/background.js

@@ -492,20 +492,26 @@ FileBrowserBackgroundImpl.prototype.onMountCompletedInternal_ = function(
     event) {
   // If there is no focused window, then create a new one opened on the
   // mounted FSP volume.
-  this.findFocusedWindow_().then(function(key) {
-    if (key === null &&
-        event.eventType === 'mount' &&
-        (event.status === 'success' ||
-         event.status === 'error_path_already_mounted') &&
-        event.volumeMetadata.mountContext === 'user' &&
-        event.volumeMetadata.volumeType ===
-            VolumeManagerCommon.VolumeType.PROVIDED &&
-        event.volumeMetadata.source === VolumeManagerCommon.Source.FILE) {
-      this.navigateToVolumeWhenReady_(event.volumeMetadata.volumeId);
-    }
-  }.bind(this)).catch(function(error) {
-    console.error(error.stack || error);
-  });
+  this.findFocusedWindow_()
+      .then(function(key) {
+        let statusOK = event.status === 'success' ||
+            event.status === 'error_path_already_mounted';
+        let volumeTypeOK =
+            event.volumeMetadata.source === VolumeManagerCommon.Source.FILE ||
+            VolumeManagerCommon.getProvidedFileSystemIdFromVolumeId(
+                event.volumeId) ===
+                VolumeManagerCommon.ProvidedFileSystem.CROSTINI;
+        if (key === null && event.eventType === 'mount' && statusOK &&
+            event.volumeMetadata.mountContext === 'user' &&
+            event.volumeMetadata.volumeType ===
+                VolumeManagerCommon.VolumeType.PROVIDED &&
+            volumeTypeOK) {
+          this.navigateToVolumeWhenReady_(event.volumeMetadata.volumeId);
+        }
+      }.bind(this))
+      .catch(function(error) {
+        console.error(error.stack || error);
+      });
 };
 
 /**

ui/file_manager/file_manager/common/js/volume_manager_common.js

@@ -102,6 +102,9 @@ VolumeManagerCommon.RootType = {
 
   // 'Add new services' menu item.
   ADD_NEW_SERVICES_MENU: 'add_new_services_menu',
+
+  // Fake root for SFTP Mount such as Linux Files.
+  SFTP_MOUNT: 'sftp_mount',
 };
 Object.freeze(VolumeManagerCommon.RootType);
 
@@ -131,6 +134,7 @@ VolumeManagerCommon.RootTypesForUMA = [
   VolumeManagerCommon.RootType.RECENT,
   VolumeManagerCommon.RootType.DRIVE_FAKE_ROOT,
   VolumeManagerCommon.RootType.ADD_NEW_SERVICES_MENU,
+  VolumeManagerCommon.RootType.SFTP_MOUNT,
 ];
 console.assert(
     Object.keys(VolumeManagerCommon.RootType).length ===
@@ -321,6 +325,26 @@ VolumeManagerCommon.getMediaViewRootTypeFromVolumeId = function(volumeId) {
       volumeId.split(':', 2)[1]);
 };
 
+
+/**
+ * List of known FSP-provided fileSystemId values.
+ *
+ * @enum {string}
+ * @const
+ */
+VolumeManagerCommon.ProvidedFileSystem = {
+  CROSTINI: 'crostini',
+};
+
+/**
+ * Obtains fileSystemId from volumeId of FSP-provided mount.
+ * @param {string} volumeId Volume ID.
+ * @return {string|undefined}
+ */
+VolumeManagerCommon.getProvidedFileSystemIdFromVolumeId = function(volumeId) {
+  return volumeId ? volumeId.split(':', 3)[2] : undefined;
+};
+
 /**
  * Fake entries for virtual folders which hold Google Drive offline files,
  * Google Drive "Shared with me" files, and mixed Recent files.

ui/file_manager/file_manager/foreground/css/file_types.css

@@ -234,7 +234,8 @@ tree .tree-item[selected] > .tree-row > .shared[file-type-icon='folder'] {
       url(../images/volumes/2x/service_drive_active.png) 2x);
 }
 
-[volume-type-icon='team_drives_grand_root'],[volume-type-icon='team_drive'] {
+[volume-type-icon='team_drives_grand_root'],
+[volume-type-icon='team_drive'] {
   background-image: -webkit-image-set(
       url(../images/volumes/team_drive.png) 1x,
       url(../images/volumes/2x/team_drive.png) 2x);
@@ -416,3 +417,20 @@ cr-menu-item[command='#install-new-extension'] .icon.start {
       url(../images/volumes/recent_active.png) 1x,
       url(../images/volumes/2x/recent_active.png) 2x);
 }
+
+[sftp-mount-icon='linux-files'],
+[volume-subtype='crostini'] {
+  /* Need !important to override inline style applied to provided volumes. */
+  background-image: -webkit-image-set(
+      url(../images/volumes/linux_files.png) 1x,
+      url(../images/volumes/2x/linux_files.png) 2x) !important;
+}
+
+.tree-row[selected] [sftp-mount-icon='linux-files'],
+.tree-row[selected] [volume-subtype='crostini'] {
+  /* Need !important to override inline style applied to provided volumes. */
+  background-image: -webkit-image-set(
+      url(../images/volumes/linux_files_active.png) 1x,
+      url(../images/volumes/2x/linux_files_active.png) 2x) !important;
+}
+

ui/file_manager/file_manager/foreground/js/directory_model.js

@@ -1164,13 +1164,15 @@ DirectoryModel.prototype.onVolumeInfoListUpdated_ = function(event) {
     }.bind(this));
   }
 
-  // If a new file backed provided volume is mounted, then redirect to it in
-  // the focused window. Note, that this is a temporary solution for
-  // crbug.com/427776.
-  if (window.isFocused() &&
-      event.added.length === 1 &&
+  // If a new file backed provided volume, or crostini is mounted,
+  // then redirect to it in the focused window.
+  // Note, that this is a temporary solution for https://crbug.com/427776.
+  if (window.isFocused() && event.added.length === 1 &&
       event.added[0].volumeType === VolumeManagerCommon.VolumeType.PROVIDED &&
-      event.added[0].source === VolumeManagerCommon.Source.FILE) {
+      (event.added[0].source === VolumeManagerCommon.Source.FILE ||
+       VolumeManagerCommon.getProvidedFileSystemIdFromVolumeId(
+           event.added[0].volumeId) ===
+           VolumeManagerCommon.ProvidedFileSystem.CROSTINI)) {
     event.added[0].resolveDisplayRoot().then(function(displayRoot) {
       // Resolving a display root on FSP volumes is instant, despite the
       // asynchronous call.

ui/file_manager/file_manager/foreground/js/navigation_list_model.js

@@ -10,6 +10,7 @@ var NavigationModelItemType = {
   VOLUME: 'volume',
   MENU: 'menu',
   RECENT: 'recent',
+  SFTP_MOUNT: 'sftp_mount',
 };
 
 /**
@@ -130,6 +131,38 @@ NavigationModelRecentItem.prototype = /** @struct */ {
   }
 };
 
+/**
+ * Item of NavigationListModel for an SFTP Mount as used by Linux files.
+ *
+ * @param {string} label Label on the item.
+ * @param {!FakeEntry} entry Fake entry for the SFTP Mount root folder.
+ * @param {string} icon CSS icon.
+ * @constructor
+ * @extends {NavigationModelItem}
+ * @struct
+ */
+function NavigationModelSFTPMountItem(label, entry, icon) {
+  NavigationModelItem.call(this, label, NavigationModelItemType.SFTP_MOUNT);
+  this.entry_ = entry;
+  this.icon_ = icon;
+}
+
+NavigationModelSFTPMountItem.prototype = /** @struct */ {
+  __proto__: NavigationModelItem.prototype,
+  get entry() {
+    return this.entry_;
+  },
+  get icon() {
+    return this.icon_;
+  },
+  /**
+   * Start crostini container and mount it.
+   */
+  mount: function() {
+    chrome.fileManagerPrivate.mountCrostiniContainer();
+  },
+};
+
 /**
  * A navigation list model. This model combines multiple models.
  * @param {!VolumeManagerWrapper} volumeManager VolumeManagerWrapper instance.
@@ -162,13 +195,20 @@ function NavigationListModel(
    */
   this.recentModelItem_ = recentModelItem;
 
+  /**
+   * Root folder for crostini Linux Files.
+   * This field will be set asynchronously after calling
+   * chrome.fileManagerPrivate.isCrostiniEnabled.
+   * @private {NavigationModelSFTPMountItem}
+   */
+  this.linuxFilesItem_ = null;
+
   /**
    * @private {NavigationModelMenuItem}
    * @const
    */
   this.addNewServicesItem_ = addNewServicesItem;
 
-
   /**
    * All root navigation items in display order.
    * @private {!Array<!NavigationModelItem>}
@@ -210,7 +250,25 @@ function NavigationListModel(
     this.shortcutList_.push(entryToModelItem(shortcutEntry));
   }
 
-  // Reorder volumes, shortcuts, and optional items.
+  // Check if crostini is enabled to create linuxFilesItem_.
+  chrome.fileManagerPrivate.isCrostiniEnabled((enabled) => {
+    if (!enabled)
+      return;
+
+    this.linuxFilesItem_ = new NavigationModelSFTPMountItem(
+        str('LINUX_FILES_ROOT_LABEL'), {
+          isDirectory: true,
+          rootType: VolumeManagerCommon.RootType.SFTP_MOUNT,
+          toURL: function() {
+            return 'fake-entry://linux-files';
+          },
+        },
+        'linux-files');
+    // Reorder items to ensure Linux Files is shown.
+    this.reorderNavigationItems_();
+  });
+
+  // Reorder volumes, shortcuts, and optional items for initial display.
   this.reorderNavigationItems_();
 
   // Generates a combined 'permuted' event from an event of either volumeList or
@@ -333,14 +391,30 @@ NavigationListModel.prototype = {
  *  1. Volumes.
  *  2. If Downloads exists, then immediately after Downloads should be:
  *  2a. Recent if it exists.
+ *  2b. Linux Files if it exists and is not mounted.
+ *      When mounted, it will be located in Volumes at this position.
  *  3. Shortcuts.
  *  4. Add new services if it exists.
  * @private
  */
 NavigationListModel.prototype.reorderNavigationItems_ = function() {
+  // Check if Linux files already mounted.
+  let linuxFilesMounted = false;
+  for (let i = 0; i < this.volumeList_.length; i++) {
+    if (VolumeManagerCommon.getProvidedFileSystemIdFromVolumeId(
+            this.volumeList_[i].volumeInfo.volumeId) ===
+        VolumeManagerCommon.ProvidedFileSystem.CROSTINI) {
+      linuxFilesMounted = true;
+      break;
+    }
+  }
+
   // Items as per required order.
   this.navigationItems_ = this.volumeList_.slice();
   var downloadsVolumeIndex = this.findDownloadsVolumeIndex_();
+  if (this.linuxFilesItem_ && !linuxFilesMounted && downloadsVolumeIndex >= 0)
+    this.navigationItems_.splice(
+        downloadsVolumeIndex + 1, 0, this.linuxFilesItem_);
   if (this.recentModelItem_ && downloadsVolumeIndex >= 0)
     this.navigationItems_.splice(
         downloadsVolumeIndex + 1, 0, this.recentModelItem_);

ui/file_manager/file_manager/foreground/js/navigation_list_model_unittest.js

@@ -11,7 +11,8 @@ var hoge;
 // Set up string assets.
 loadTimeData.data = {
   DRIVE_DIRECTORY_LABEL: 'My Drive',
-  DOWNLOADS_DIRECTORY_LABEL: 'Downloads'
+  DOWNLOADS_DIRECTORY_LABEL: 'Downloads',
+  LINUX_FILES_ROOT_LABEL: 'Linux Files',
 };
 
 function setUp() {
@@ -19,6 +20,15 @@ function setUp() {
   // Override VolumeInfo.prototype.resolveDisplayRoot.
   VolumeInfoImpl.prototype.resolveDisplayRoot = function() {};
 
+  // Mock chrome.fileManagerPrivate.isCrostiniEnabled.
+  // TODO(crbug.com/834103): Add integration test for Crostini.
+  chrome.fileManagerPrivate = {
+    crostiniEnabled: false,
+    isCrostiniEnabled: function(callback) {
+      callback(this.crostiniEnabled);
+    },
+  };
+
   drive = new MockFileSystem('drive');
   hoge = new MockFileSystem('removable:hoge');
 }
@@ -33,22 +43,24 @@ function testModel() {
     }
   };
   var recentItem = new NavigationModelRecentItem('recent-label', fakeEntry);
+  chrome.fileManagerPrivate.crostiniEnabled = true;
   var addNewServicesItem = new NavigationModelMenuItem(
       'menu-button-label', '#add-new-services', 'menu-button-icon');
   var model = new NavigationListModel(
       volumeManager, shortcutListModel, recentItem, addNewServicesItem);
 
-  assertEquals(5, model.length);
+  assertEquals(6, model.length);
   assertEquals('drive', model.item(0).volumeInfo.volumeId);
   assertEquals('downloads', model.item(1).volumeInfo.volumeId);
   assertEquals('fake-entry://recent', model.item(2).entry.toURL());
-  assertEquals('/root/shortcut', model.item(3).entry.fullPath);
-  assertEquals('menu-button-label', model.item(4).label);
-  assertEquals('#add-new-services', model.item(4).menu);
-  assertEquals('menu-button-icon', model.item(4).icon);
+  assertEquals('fake-entry://linux-files', model.item(3).entry.toURL());
+  assertEquals('/root/shortcut', model.item(4).entry.fullPath);
+  assertEquals('menu-button-label', model.item(5).label);
+  assertEquals('#add-new-services', model.item(5).menu);
+  assertEquals('menu-button-icon', model.item(5).icon);
 }
 
-function testNoRecent() {
+function testNoRecentOrLinuxFiles() {
   var volumeManager = new MockVolumeManagerWrapper();
   var shortcutListModel = new MockFolderShortcutDataModel(
       [new MockFileEntry(drive, '/root/shortcut')]);

ui/file_manager/file_manager/foreground/js/ui/directory_tree.js

@@ -700,6 +700,13 @@ VolumeItem.prototype.setupIcon_ = function(icon, volumeInfo) {
         'volume-subtype',
         VolumeManagerCommon.getMediaViewRootTypeFromVolumeId(
             volumeInfo.volumeId));
+  } else if (
+      volumeInfo.volumeType === VolumeManagerCommon.VolumeType.PROVIDED) {
+    icon.setAttribute(
+        'volume-subtype',
+        VolumeManagerCommon.getProvidedFileSystemIdFromVolumeId(
+            volumeInfo.volumeId) ||
+            '');
   } else {
     icon.setAttribute('volume-subtype', volumeInfo.deviceType || '');
   }
@@ -1184,6 +1191,54 @@ RecentItem.prototype.activate = function() {
   this.parentTree_.directoryModel.activateDirectoryEntry(this.entry);
 };
 
+////////////////////////////////////////////////////////////////////////////////
+// SFTPMountItem
+
+/**
+ * A TreeItem which represents a directory to be mounted using SFTP.
+ *
+ * @param {!NavigationModelSFTPMountItem} modelItem
+ * @param {!DirectoryTree} tree Current tree, which contains this item.
+ * @extends {cr.ui.TreeItem}
+ * @constructor
+ */
+function SFTPMountItem(modelItem, tree) {
+  var item = new cr.ui.TreeItem();
+  item.__proto__ = SFTPMountItem.prototype;
+
+  item.parentTree_ = tree;
+  item.modelItem_ = modelItem;
+  item.innerHTML = TREE_ITEM_INNER_HTML;
+  item.label = modelItem.label;
+
+  var icon = queryRequiredElement('.icon', item);
+  icon.classList.add('item-icon');
+  icon.setAttribute('sftp-mount-icon', item.modelItem_.icon);
+
+  return item;
+}
+
+SFTPMountItem.prototype = {
+  __proto__: cr.ui.TreeItem.prototype,
+  get entry() {
+    return null;
+  },
+  get modelItem() {
+    return this.modelItem_;
+  },
+  get labelElement() {
+    return this.firstElementChild.querySelector('.label');
+  }
+};
+
+/**
+ * @override
+ */
+SFTPMountItem.prototype.handleClick = function(e) {
+  this.selected = true;
+  this.modelItem_.mount();
+};
+
 
 ////////////////////////////////////////////////////////////////////////////////
 // DirectoryTree
@@ -1373,6 +1428,9 @@ DirectoryTree.prototype.updateSubElementsFromList = function(recursive) {
         case NavigationModelItemType.RECENT:
           this.addAt(new RecentItem(modelItem, this), itemIndex);
           break;
+        case NavigationModelItemType.SFTP_MOUNT:
+          this.addAt(new SFTPMountItem(modelItem, this), itemIndex);
+          break;
       }
     }
     itemIndex++;

ui/file_manager/file_manager/test/js/strings.js

@@ -53,6 +53,7 @@ loadTimeData.data = new Proxy(
           'utm_campaign=gsg',
       IMAGE_FILE_TYPE: '$1 image',
       INSTALL_NEW_EXTENSION_LABEL: 'Install new from the webstore',
+      LINUX_FILES_ROOT_LABEL: 'Linux Files',
       MANY_ENTRIES_SELECTED: '$1 items selected',
       MANY_FILES_SELECTED: '$1 files selected',
       METADATA_BOX_ALBUM_TITLE: 'Album',
@@ -68,6 +69,8 @@ loadTimeData.data = new Proxy(
       OPEN_LABEL: 'Open',
       PLAIN_TEXT_FILE_TYPE: 'Plain text',
       PREPARING_LABEL: 'Preparing',
+      SEE_MENU_FOR_ACTIONS: 'More options available on the action bar. ' +
+          'Press Alt + A to focus the action bar.',
       SIZE_COLUMN_LABEL: 'Size',
       SPACE_AVAILABLE: '$1 available',
       STATUS_COLUMN_LABEL: 'Status',