ENYO-3608: restore icon setting to the right resource

Related JIRA: 
* https://enyojs.atlassian.net/browse/ENYO-3608
* https://enyojs.atlassian.net/browse/ENYO-3604

Actions:
* ENYO-3608: filetree icon resource name was not updated, so related icon was missing
* ENYO-3604: Due to an obsolete asynchronicity security around project context loading, the _FileChooser_ widget wasn't able to allow user to double click on folder name label in order to expand it.

Enyo-DCO-1.1-Signed-off-by: Vincent HERILIER vincent.herilier@hp.com