Capture $VERBOSE early for ruby 1.8 and syck

I'm not sure how, but syck also disables warnings in a similar way and
this interfered with RubyGems enabling syck for tests.  This would cause
the contains_requirable_file? tests to fail on ruby 1.8 when ran after
with_syck.

test/rubygems/test_gem_specification.rb

@@ -2948,9 +2948,9 @@ def util_setup_validate
 
   def with_syck
     begin
+      verbose, $VERBOSE = $VERBOSE, nil
       require "yaml"
       old_engine = YAML::ENGINE.yamler
-      verbose, $VERBOSE = $VERBOSE, nil
       YAML::ENGINE.yamler = 'syck'
       load 'rubygems/syck_hack.rb'
     rescue NameError