allow to access saved report after associated task deleted

BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1450272

app/controllers/report_controller/saved_reports.rb

@@ -25,8 +25,7 @@ def fetch_saved_report(id)
     if admin_user? || current_user.miq_group_ids.include?(rr.miq_group_id)
       @report_result_id = session[:report_result_id] = rr.id
       session[:report_result_runtime] = rr.last_run_on
-      task = MiqTask.find_by_id(rr.miq_task_id)
-      if rr.status.downcase == "complete"
+      if report_finished?(rr)
         @report = rr.report_results
         session[:rpt_task_id] = nil
         if @report.blank?
@@ -139,6 +138,14 @@ def get_all_saved_reports
 
   private
 
+  def report_finished?(report_result)
+    if MiqTask.exists?(report_result.miq_task_id)
+      report_result.status.downcase == "complete"
+    else
+      !report_result.last_run_on.blank?
+    end
+  end
+
   # Build the main Saved Reports tree
   def build_savedreports_tree
     TreeBuilderReportSavedReports.new('savedreports_tree', 'savedreports', @sb)