Created attachment 1078673 [details]
Error message when refreshing the problems panel

Description of problem:
When the deployment is unsuccessfully undeployed and problems panel is refreshed it fails with the error message. 

Version-Release number of selected component (if applicable):
BPMS 6.2.0.ER4

How reproducible:
Always

Steps to Reproduce:
1. Go to Deployments perspective
2. try to Undeploy a deployment with running process instances
3. Go to the problems panel and hit the Refresh button

Actual results:
Modal dialog with Error message: Unable to complete your request. The following exception occurred: null.

Expected results:
Problems panel is refreshed

Additional info:
ERROR [org.kie.workbench.common.services.backend.builder.BuildServiceImpl] (http-/127.0.0.1:8080-24) Parameter named 'path' should be not null!: java.lang.IllegalArgumentException: Parameter named 'path' should be not null!
	at org.uberfire.commons.validation.PortablePreconditions.checkNotNull(PortablePreconditions.java:119) [uberfire-commons-0.7.2.Final-redhat-1.jar:0.7.2.Final-redhat-1]
	at org.guvnor.common.services.backend.cache.LRUCache.invalidateCache(LRUCache.java:70) [guvnor-services-api-6.3.0.Final-redhat-1.jar:6.3.0.Final-redhat-1]
	at org.kie.workbench.common.services.backend.builder.LRUBuilderCache$Proxy$_$$_WeldClientProxy.invalidateCache(LRUBuilderCache$Proxy$_$$_WeldClientProxy.java) [kie-wb-common-services-backend-6.3.0.Final-redhat-1.jar:6.3.0.Final-redhat-1]