* vm_insnhelper.c (vm_call_method_each_type): should not set fastpath
	  with keyword arguments for VM_METHOD_TYPE_ATTRSET type methods.
	  Normally, we can not use keyword arguments for this kind of methods,
	  (obj.foo = 1), but we can set alias names for them.
	  [Bug #11657]

	* test/ruby/test_keyword.rb: add a test for this fix.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_2@53567 b2dd03c8-39d4-4d8f-98ff-823fe69b080e