- Remove check for .b method. (tenderlove)

[git-p4: depot-paths = "//src/minitest/dev/": change = 13574]

lib/minitest.rb

@@ -823,7 +823,7 @@ def aggregated_results io # :nodoc:
     end
 
     def to_s # :nodoc:
-      aggregated_results(StringIO.new(binary_string)).string
+      aggregated_results(StringIO.new(''.b)).string
     end
 
     def summary # :nodoc:
@@ -836,14 +836,6 @@ def summary # :nodoc:
       "%d runs, %d assertions, %d failures, %d errors, %d skips%s" %
         [count, assertions, failures, errors, skips, extra]
     end
-
-    private
-
-    if '<3'.respond_to? :b
-      def binary_string; ''.b; end
-    else
-      def binary_string; ''.force_encoding(Encoding::ASCII_8BIT); end
-    end
   end
 
   ##