Does Wings of Liberty have global play on its own?

I just learnt that global play is available in Heart of the Swarm. If I only have a Wings of Liberty copy attached to the North American server and I have a friend with only a Wings of Liberty copy attached to the European server, can we both use global play to play together without Heat of the Swarm?

Yes, Wings of Liberty has global play without upgrading to Heart of the Swarm.

If I want to use Global Play, do I have to upgrade to Heart of the Swarm?.

Global play will be available to all StarCraft II players, regardless of license level. You do not need to upgrade your copy of Wings of Liberty to use Global Play.

If you have more than one regional copy of Wings of Liberty and want to upgrade to Heart of the Swarm, you only need to upgrade one of them. The Heart of the Swarm upgrade applies to all regional versions of Wings of Liberty on your Battle.net account.

Source: Global Play FAQ from Battle.net

As has been mentioned and is also in the FAQ, Global Play is not available to those in mainland China.

In patch 2.0.5 of Wings of Liberty Global play was enabled.

GENERAL

• Global Play is now live.
  • Players can now easily switch between regions via the new “Regions” button on the StarCraft II login screen.
  • Your game language and user interface will not change when you change regions.
  • Your character profiles and ladder data are unique to each region.
  • When your region’s game servers are undergoing maintenance, you may be able to play in a different region that is not down for maintenance.
  • For more information, please visit our Global Play FAQ on our support site.

Yes, it is available, except for players in mainland China

Following numerous complaints earlier today about having problems with logging in or downloading Battle.net data players are now able to play full version of Wings of Liberty on servers other than their original license is for. For example EU players are free to log in and create fully functional character on NA and vice versa, provided they have appropriate game client.

Source: TeamLiquid's thread