* gc.c (heap_page_resurrect): do not return tomb_pages when
	  page->freelist == NULL.
	  [Bug #12670]

	test for [Bug #12670]

	heap corruption by deferred free.
	gc.c: expand sorted pages

	* gc.c (heap_page_allocate): expand sorted pages before inserting
	  allocated new page.  [Bug #12670]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_3@59234 b2dd03c8-39d4-4d8f-98ff-823fe69b080e