Original array is overwritten when select! is called on a copy

1. Sample code that shows the problem (test.rb):
2. Create an array

   array = %w(value1 value2 a_value value2)

3. Print the whole array

   puts array.inspect

4. Copy and modify an array

   new_array = Array.new(array)
   new_array.select! { |element| element.start_with?("value") }
   puts new_array.inspect
   puts array.inspect
   

5. Output of the above code:

   jruby --1.9 test.rb
   ["value1", "value2", "a_value", "value2"]
   ["value1", "value2", "value2"]
   ["value1", "value2", "value2", "value2"]
   

   rvm use 1.9.3
   ruby test.rb
   ["value1", "value2", "a_value", "value2"]
   ["value1", "value2", "value2"]
   ["value1", "value2", "a_value", "value2"]
   

A GitHub pull request to fix this issue:
https://github.com/jruby/jruby/pull/114