Add a refresh button for providers which do not support watchers.

ui/file_manager/file_manager/background/js/volume_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.
 
 /**
  * Represents each volume, such as "drive", "download directory", each "USB
  * flush storage", or "mounted zip archive" etc.
  *
  * @constructor
  * @struct
@@ skipping 24 matching lines @@
     fileSystem,
     error,
     deviceType,
     devicePath,
     isReadOnly,
     profile,
     label,
     extensionId,
     hasMedia,
     configurable,
+    watchable,
     source) {
   this.volumeType_ = volumeType;
   this.volumeId_ = volumeId;
   this.fileSystem_ = fileSystem;
   this.label_ = label;
   this.displayRoot_ = null;
 
   /** @type {Object<!FakeEntry>} */
   this.fakeEntries_ = {};
 
@@ skipping 23 matching lines @@
   // or not. (If error is empty string, the mount is successfully done).
   // TODO(hidehiko): Rename to make this more understandable.
   this.error_ = error;
   this.deviceType_ = deviceType;
   this.devicePath_ = devicePath;
   this.isReadOnly_ = isReadOnly;
   this.profile_ = Object.freeze(profile);
   this.extensionId_ = extensionId;
   this.hasMedia_ = hasMedia;
   this.configurable_ = configurable;
+  this.watchable_ = watchable;
   this.source_ = source;
 }
 
 VolumeInfo.prototype = /** @struct */ {
   /**
    * @return {VolumeManagerCommon.VolumeType} Volume type.
    */
   get volumeType() {
     return this.volumeType_;
   },
@@ skipping 70 matching lines @@
   get hasMedia() {
     return this.hasMedia_;
   },
   /**
    * @return {boolean} True if the volume is configurable.
    */
   get configurable() {
     return this.configurable_;
   },
   /**
+   * @return {boolean} True if the volume is watchable.
+   */
+  get watchable() {
+    return this.watchable_;
+  },
+  /**
    * @return {VolumeManagerCommon.Source} Source of the volume's data.
    */
   get source() {
     return this.source_;
   }
 };
 
 /**
  * Starts resolving the display root and obtains it.  It may take long time for
  * Drive. Once resolved, it is cached.
@@ skipping 138 matching lines @@
             fileSystem,
             volumeMetadata.mountCondition,
             volumeMetadata.deviceType,
             volumeMetadata.devicePath,
             volumeMetadata.isReadOnly,
             volumeMetadata.profile,
             localizedLabel,
             volumeMetadata.extensionId,
             volumeMetadata.hasMedia,
             volumeMetadata.configurable,
+            volumeMetadata.watchable,
             /** @type {VolumeManagerCommon.Source} */
             (volumeMetadata.source));
   })
   .catch(
       /**
        * @param {*} error
        */
       function(error) {
         console.error('Failed to mount a file system: ' +
             volumeMetadata.volumeId + ' because of: ' +
             (error.stack || error));
         return new VolumeInfo(
             /** @type {VolumeManagerCommon.VolumeType} */
             (volumeMetadata.volumeType),
             volumeMetadata.volumeId,
             null,  // File system is not found.
             volumeMetadata.mountCondition,
             volumeMetadata.deviceType,
             volumeMetadata.devicePath,
             volumeMetadata.isReadOnly,
             volumeMetadata.profile,
             localizedLabel,
             volumeMetadata.extensionId,
             volumeMetadata.hasMedia,
             volumeMetadata.configurable,
+            volumeMetadata.watchable,
             /** @type {VolumeManagerCommon.Source} */
             (volumeMetadata.source));
       });
 };
 
 /**
  * The order of the volume list based on root type.
  * @type {Array<VolumeManagerCommon.VolumeType>}
  * @const
  * @private
@@ skipping 749 matching lines @@
       this.isDriveBased;
 
   /**
    * Whether the entry is read only or not.
    * @type {boolean}
    */
   this.isReadOnly = isReadOnly;
 
   Object.freeze(this);
 }