Merge pull request #9610 from jrafanie/support-rexml-3-4-3

rexml 3.4.3 Document.new no longer accepts strings with no root element

Author: Fryguy

app/controllers/miq_ae_class_controller.rb

@@ -401,7 +401,7 @@ def class_and_glyph(cls)
   end
 
   def build_details_grid(view, mode = true)
-    xml = REXML::Document.load("")
+    xml = REXML::Document.load(nil)
     xml << REXML::XMLDecl.new(1.0, "UTF-8")
 
     # Create root element