* lib/rubygems: Update to RubyGems 2.4.1 master(713ab65)

Complete history at:
  https://github.com/rubygems/rubygems/blob/master/History.txt#L3-L216
* test/rubygems:  ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47582 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/rubygems/resolver/api_specification.rb

@@ -34,6 +34,12 @@ class Gem::Resolver::APISpecification < Gem::Resolver::Specification
       @dependencies == other.dependencies
   end
 
+  def fetch_development_dependencies # :nodoc:
+    spec = source.fetch_spec Gem::NameTuple.new @name, @version, @platform
+
+    @dependencies = spec.dependencies
+  end
+
   def installable_platform? # :nodoc:
     Gem::Platform.match @platform
   end