RevealResourceAction and "Link with Editor" button work incorrect

[AndrienkoAleksandr]

Reproduction Steps:
Steps to Reproduce:

1. Create Spring project from template.
2. Open index.jsp file.
3. Close project Spring in the ProjectExplorer.
4. Click "Link with Editor" in the ProjectExplorer.
5. Click editor index.jsp
   Expected behavior: ProjectExplorer should expand index.jsp node.
   Actual behavior: ProjectExplorer fails:
   Uncaught (in promise) Error: com.google.gwt.event.shared.UmbrellaException: Exception caught: (TypeError) : Cannot read property 'className' of null
   at UmbrellaException_0.createError (Throwable.java:121)
   at UmbrellaException_0.initializeBackingError (Throwable.java:113)
   at UmbrellaException_0.Throwable_2 (Throwable.java:74)
   at UmbrellaException_0.Exception_2 (Exception.java:33)
   at UmbrellaException_0.RuntimeException_2 (RuntimeException.java:33)
   at UmbrellaException_0.UmbrellaException (UmbrellaException.java:65)
   at UmbrellaException_0 (UmbrellaException.java:26)
   at SimpleEventBus_1.castFireEvent (EventBus.java:69)
   at SimpleEventBus_1.fireEvent_3 [as fireEvent_0] (SimpleEventBus.java:57)
   at NodeLoader_0.fireEvent_12 [as fireEvent_1] (NodeLoader.java:361)
   at NodeLoader_0.onLoadSuccess (NodeLoader.java:329)
   at NodeLoader_0.iterate (NodeLoader.java:410)
   at NodeLoader$7.apply_742 [as apply_27] (NodeLoader.java:422)
   at NodeLoader$7.apply_741 [as apply_8] (NodeLoader.java:421)
   at JsPromise.java:118
   at
   createError @ Throwable.java:121
   initializeBackingError @ Throwable.java:113
   Throwable_2 @ Throwable.java:74
   Exception_2 @ Exception.java:33
   RuntimeException_2 @ RuntimeException.java:33
   UmbrellaException @ UmbrellaException.java:65
   UmbrellaException_0 @ UmbrellaException.java:26
   castFireEvent @ EventBus.java:69
   fireEvent_3 @ SimpleEventBus.java:57
   fireEvent_12 @ NodeLoader.java:361
   onLoadSuccess @ NodeLoader.java:329
   iterate @ NodeLoader.java:410
   apply_742 @ NodeLoader.java:422
   apply_741 @ NodeLoader.java:421
   (anonymous) @ JsPromise.java:118

OS and version:
Fedora 25.
Version:
5.18.0-SNAPSHOT

[AndrienkoAleksandr]

Seems related #6289

[riuvshin]

PR merged, should we close this issue?