merge revision(s) 48000: [Backport #10368]

	* vm_core.h, vm.c, proc.c: fix GC mark miss on bindings.
	  [ruby-dev:48616] [Bug #10368]

	* test/ruby/test_eval.rb: add a test code.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@48048 b2dd03c8-39d4-4d8f-98ff-823fe69b080e