Fix a small bug in bookmarks_bridge.cc

While fetching the node_id and type from java bookmark object, we fallback
to the mobile bookmarks folder in case the value in the invalid -1. We need
to update the java bookmark object to reflect this change before passing it
back.

BUG=316405

Review URL: https://codereview.chromium.org/61873005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@235499 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 235499