Remove call unneeded Attached() method call for Smb Dialog

This change removes the attached method override from the smb-share-dialog
component.

Bug: chromium:887135
Change-Id: Id6a7b06a2b2b9ea4d0da5dc04cb14f7143c0c312
Reviewed-on: https://chromium-review.googlesource.com/c/1340860
Commit-Queue: Bailey Berro <baileyberro@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#613271}

chrome/browser/resources/chromeos/smb_shares/smb_share_dialog.js

@@ -13,11 +13,6 @@ Polymer({
 
   behaviors: [I18nBehavior],
 
-  /** @override */
-  attached: function() {
-    this.$.addShareDialog.open();
-  },
-
   /** @private */
   onDialogClose_: function() {
     chrome.send('dialogClose');