Handle frontend folder from different locations

[qtdzz]

Steps to reproduce

1. Pull the latest master of bakery-flow-spring project
2. Create a design

Actual behavior

• Designer suggests creating a design at src/main/webapp/frontend while all of the other designs are in resource/static/frontend
• The polymer import is <link rel="import" href="../../../../../../webapp/frontend/bower_components/polymer/polymer.html">

Expected behavior

• Designer will suggest the place where all other designs are located
• Import link should look better

IDE, Designer and OS version

IntelliJ, Designer 3.0.5, Linux

[szolo]

Alex (@alexberazouski) from Pro also confirmed that even our existing behavior is strange sometimes. After right-clicking on some folder he was expecting this folder to be proposed in "New Design" wizard. Instead some default value was used. Moreover, directory for this default value hasn't existed in the project. We need to improve our wizard logic.

👍

[ripla]

Prioritised. The wizard should adhere to the existing spec and all should be well:

• 
• 
• 
• 

Also updated the path in the Spring scenario

[szolo]

Erik (@eriklumme) also reported couple of issues with existing Vaadin Spring starter:

1. When creating a new Design folder webapp/frontend is proposed instead of webapp/frontend/src.
2. Shared styles couldn't be found in path src/main/resources/META-INF/resources/frontend/styles/shared-styles.html.

shared-styles.html should be considered in this card as well since they also reside inside frontend folder.

[ripla]

@szolo good additions. I don't think the webapp/frontend/src is valid though. frontend is a folder that has special meaning for Flow, while src is just a convention. We could still offer it but I wouldn't say it's necessary.

[ripla]

Related: https://spring.io/blog/2013/12/19/serving-static-web-content-with-spring-boot

[ripla]

#1612
#1613