merge revision(s) 41300: [Backport #8489]

	* compile.c (rb_iseq_compile_node): fix location of a `trace'
	  instruction (b_return event).
	  [ruby-core:55305] [ruby-trunk - Bug #8489]
	  (need a backport to 2.0.0?)

	* test/ruby/test_settracefunc.rb: add a test.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@41319 b2dd03c8-39d4-4d8f-98ff-823fe69b080e