Remove backtrace cleaner specific to Bundler. Bundler just uses Gem.dir and Gem.path now.

railties/lib/rails/backtrace_cleaner.rb

@@ -12,7 +12,6 @@ module Rails
       add_filter   { |line| line.sub('./', '/') } # for tests
 
       add_gem_filters
-      add_bundler_filters
 
       add_silencer { |line| !APP_DIRS.any? { |dir| line =~ /^#{dir}/ } }
     end
@@ -27,16 +26,6 @@ module Rails
           }
         end
       end
-
-      def add_bundler_filters
-        return unless defined? Bundler
-        add_filter { |line|
-          line.sub(%r{vendor/gems/[^/]+/[^/]+/gems/([^/]+)-([0-9.]+)/(.*)}, '\1 (\2) \3')
-        }
-        add_filter { |line|
-          line.sub(%r{vendor/gems/[^/]+/[^/]+/dirs/([^/]+)/(.*)}, '\1 \2')
-        }
-      end
   end
 
   # For installing the BacktraceCleaner in the test/unit