* lib/rubygems: Update to RubyGems master dcce4ff. Important changes

in this commit:

  Remove automatic detection of gem dependencies files.  This prevents a
  security hole as described in [ruby-core:58490]

  Fixed bugs for installing git gems.

* test/rubygems:  ditto.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43806 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/rubygems/test_gem_specification.rb

@@ -1738,6 +1738,10 @@ dependencies: []
     RbConfig::CONFIG['ENABLE_SHARED'] = enable_shared
   end
 
+  def test_source
+    assert_kind_of Gem::Source::Installed, @a1.source
+  end
+
   def test_full_require_paths
     ext_spec