Merge RubyGems upstream: 56c0bbb69e4506bda7ef7f447dfec5db820df20b

It fixed the multiple vulnerabilities.
  https://blog.rubygems.org/2019/03/05/security-advisories-2019-03.html

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67168 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/rubygems/resolver/activation_request.rb

@@ -77,7 +77,7 @@ class Gem::Resolver::ActivationRequest
   # The full name of the specification to be activated.
 
   def full_name
-    @spec.full_name
+    name_tuple.full_name
   end
 
   alias_method :to_s, :full_name
@@ -183,4 +183,17 @@ class Gem::Resolver::ActivationRequest
     @spec.version
   end
 
+  ##
+  # The platform of this activation request's specification
+
+  def platform
+    @spec.platform
+  end
+
+  private
+
+  def name_tuple
+    @name_tuple ||= Gem::NameTuple.new(name, version, platform)
+  end
+
 end