Modify DeviceHandler to handle deviceFail event and add a message.

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

Index: ui/file_manager/file_manager/background/js/device_handler.js
diff --git a/ui/file_manager/file_manager/background/js/device_handler.js b/ui/file_manager/file_manager/background/js/device_handler.js
index c24ce08f5133ea430e4b2f778406c0f40655587b..6c89d7dcc3946d534400f4b2daafeb0a8d482d69 100644
--- a/ui/file_manager/file_manager/background/js/device_handler.js
+++ b/ui/file_manager/file_manager/background/js/device_handler.js
@@ -350,6 +350,12 @@ DeviceHandler.prototype.onMountCompleted_ = function(event) {
       }
     }
   }
+  else if (event.status === 'error_unknown_filesystem') {

[hirono, 2014/08/22 06:59:24]

else should be put at #352 after '}'.

[iseki, 2014/08/25 04:49:25]

Done.

+    // The volume id is necessary to navigate when users click start
+    // format button.
+    this.navigationVolumes_[event.volumeMetadata.devicePath] =
+      event.volumeMetadata.volumeId;
+  }
 
   if (event.eventType === 'unmount') {
     this.navigationVolumes_[volume.devicePath] = null;
@@ -406,6 +412,12 @@ DeviceHandler.prototype.onMountCompleted_ = function(event) {
   if (event.eventType === 'unmount')
     return;
 
+  // If DEVICE_UNKNOWN_MESSAGE error was occurred previously, buttonLabel has
+  // DEVICE_UNKNOWN_BUTTON_LABEL. However this label is not used for other
+  // error.
+  if (DeviceHandler.Notification.DEVICE_FAIL.buttonLabel) {

[hirono, 2014/08/22 06:59:24]

Could you add new notification type (Notification.DEVICE_FAIL_UNKNOWN) instead
changing buttonLabel?
Because DeviceHandler.Notification.DEVICE_FAIL is global instance, I'd like keep
it readonly.

[iseki, 2014/08/25 04:49:25]

Done.

+    DeviceHandler.Notification.DEVICE_FAIL.buttonLabel = null;
+  }
   // Show the notification for the current errors.
   // If there is no error, do not show/update the notification.
   var message;
@@ -425,6 +437,8 @@ DeviceHandler.prototype.onMountCompleted_ = function(event) {
         message = volume.deviceLabel ?
             strf('DEVICE_UNKNOWN_MESSAGE', volume.deviceLabel) :
             str('DEVICE_UNKNOWN_DEFAULT_MESSAGE');
+            DeviceHandler.Notification.DEVICE_FAIL.buttonLabel =
+              'DEVICE_UNKNOWN_BUTTON_LABEL'

[hirono, 2014/08/22 06:59:24]

The depth of indent should be 4 when wrapping a line.

[iseki, 2014/08/25 04:49:25]

Done.

       }
       break;
   }
@@ -440,13 +454,21 @@ DeviceHandler.prototype.onMountCompleted_ = function(event) {
  * @private
  */
 DeviceHandler.prototype.onNotificationButtonClicked_ = function(id) {
-  var match = /^deviceNavigation:(.*)$/.exec(id);
-  if (match) {
-    chrome.notifications.clear(id, function() {});
-    var event = new Event(DeviceHandler.VOLUME_NAVIGATION_REQUESTED);
-    event.volumeId = this.navigationVolumes_[match[1]];
-    this.dispatchEvent(event);
+  var pos = id.indexOf(':');
+  var type = id.substr(0, pos);
+  var path = id.substr(pos+1);
+  chrome.notifications.clear(id, function() {});
+  var event;
+  switch (type) {
+    case 'deviceNavigation':
+    case 'deviceFail':
+      event = new Event(DeviceHandler.VOLUME_NAVIGATION_REQUESTED);
+      break;
+    default:
+      return;
   }
+  event.volumeId = this.navigationVolumes_[path];

[hirono, 2014/08/22 06:59:24]

Could you follow #470 and #471 after #465?
Currently there is no reason to split it into two parts.

[iseki, 2014/08/25 04:49:25]

Done.

+  this.dispatchEvent(event);
 };
 
 DeviceHandler.prototype.onStartup_ = function() {