merge revision(s) 42782,42799: [Backport #8902]

	* vm_insnhelper.c (vm_search_super_method): use ci->argc instead of
	  ci->orig_argc. ci->argc can be changed by splat arguments.
	  [ruby-list:49575]
	  This fix should be applied to Ruby 2.0.0 seriese.

	* test/ruby/test_super.rb: add a test for above.

	* numeric.c (NUM_STEP_SCAN_ARGS): On second thought, keep

	* internal.h (bit_length): Add casts to fix compilation error with
	  This fix should be applied to Ruby 2.0.0 series.
	  numeric literal, for the backward compatibility.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@42934 b2dd03c8-39d4-4d8f-98ff-823fe69b080e