Backport CMS-6393 to 7.6: Exceptions while uploading an image in CMS

Refer CMS-6393 for more details

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Below exceptions are thrown when user attempts to upload attached image in 7.6 (CMS 2.20.12)

[INFO] [talledLocalContainer] 13.09.2012 17:21:22 ERROR [org.hippoecm.frontend.plugins.gallery.GalleryWorkflowPlugin.createGalleryItem():189] upload of image failed
[INFO] [talledLocalContainer] javax.jcr.InvalidItemStateException: Item does not exist anymore: 2e5f3221-2d5c-4222-84c4-b2d88b8e35cb
[INFO] [talledLocalContainer] at org.apache.jackrabbit.core.ItemImpl.itemSanityCheck(ItemImpl.java:116)
[INFO] [talledLocalContainer] at org.apache.jackrabbit.core.ItemImpl.perform(ItemImpl.java:90)
[INFO] [talledLocalContainer] at org.apache.jackrabbit.core.ItemImpl.getPath(ItemImpl.java:376)
[INFO] [talledLocalContainer] at org.hippoecm.repository.decorating.ItemDecorator.getPath(ItemDecorator.java:91)
[INFO] [talledLocalContainer] at org.hippoecm.repository.decorating.checked.ItemDecorator.getPath(ItemDecorator.java:92)
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.gallery.GalleryWorkflowPlugin.createGalleryItem(GalleryWorkflowPlugin.java:183)
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.gallery.GalleryWorkflowPlugin.access$100(GalleryWorkflowPlugin.java:70)
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.gallery.GalleryWorkflowPlugin$UploadDialog.handleUploadItem(GalleryWorkflowPlugin.java:92)
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.yui.upload.MultiFileUploadDialog$2.onFileUpload(MultiFileUploadDialog.java:66)
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.yui.upload.FileUploadWidget$1.onFileUpload(FileUploadWidget.java:108)
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.yui.upload.ajax.AjaxMultiFileUploadComponent$UploadBehavior.onRequest(AjaxMultiFileUploadComponent.java:68)
[INFO] [talledLocalContainer] at org.apache.wicket.request.target.component.listener.BehaviorRequestTarget.processEvents(BehaviorRequestTarget.java:157)
[INFO] [talledLocalContainer] at org.apache.wicket.request.AbstractRequestCycleProcessor.processEvents(AbstractRequestCycleProcessor.java:92)
[INFO] [talledLocalContainer] at org.hippoecm.frontend.PluginRequestCycleProcessor.processEvents(PluginRequestCycleProcessor.java:95)
[INFO] [talledLocalContainer] at org.apache.wicket.RequestCycle.processEventsAndRespond(RequestCycle.java:1250)
[INFO] [talledLocalContainer] at org.apache.wicket.RequestCycle.step(RequestCycle.java:1329)
[INFO] [talledLocalContainer] at org.apache.wicket.RequestCycle.steps(RequestCycle.java:1436)
[INFO] [talledLocalContainer] at org.apache.wicket.RequestCycle.request(RequestCycle.java:545)
[INFO] [talledLocalContainer] at org.apache.wicket.protocol.http.WicketFilter.doGet(WicketFilter.java:486)
[INFO] [talledLocalContainer] at org.apache.wicket.protocol.http.WicketFilter.doFilter(WicketFilter.java:319)
[INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
[INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
[INFO] [talledLocalContainer] at org.hippoecm.frontend.ResourceRewriteFilter.doFilter(ResourceRewriteFilter.java:129)
[INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
[INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.login.ConcurrentLoginFilter.doFilter(ConcurrentLoginFilter.java:54)
[INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
[INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
[INFO] [talledLocalContainer] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
[INFO] [talledLocalContainer] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
[INFO] [talledLocalContainer] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
[INFO] [talledLocalContainer] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
[INFO] [talledLocalContainer] at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:589)
[INFO] [talledLocalContainer] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
[INFO] [talledLocalContainer] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:291)
[INFO] [talledLocalContainer] at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
[INFO] [talledLocalContainer] at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602)
[INFO] [talledLocalContainer] at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
[INFO] [talledLocalContainer] at java.lang.Thread.run(Thread.java:662)