[DRE-maint] Bug#701629: Possible workaround

[Bastian Neuburger]

Hi,

by replacing the file /usr/lib/ruby/vendor_ruby/chef/json_compat.rb, 
which is part of the chef package, with the one at
https://github.com/opscode/chef/blob/834d814400a8a23ee8d865fa9d48e3f71895cd42/chef/lib/chef/json_compat.rb 
I could get chef-client to work with the ruby-json 1.7.3-3.

However I am not sure if this has negative side effects in some scenarios.

It seems that they switched JSON parsers from ::JSON.parse to 
::Yajl::Parser.parse.

Cheers,

Bastian