merge revision(s) 41343,41360,41386: [Backport #8531]

	test/ruby/test_symbol.rb: tests for [Bug #8531]
	* include/ruby/ruby.h, vm_eval.c (rb_funcall_with_block):
	  new function to invoke a method with a block passed
	  as an argument.

	* string.c (sym_call): use the above function to avoid
	  a block sharing. [ruby-dev:47438] [Bug #8531]

	* vm_insnhelper.c (vm_yield_with_cfunc): don't set block
	  in the frame.

	* test/ruby/test_symbol.rb (TestSymbol#test_block_given_to_proc):
	  run related tests.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@41393 b2dd03c8-39d4-4d8f-98ff-823fe69b080e