GitLab

> cc: Cancel and re-prioritize worker pool tasks.
> 
> This adds a task graph interface to the worker pool and
> implements a simple queue instance of this interface for
> use by the tile manager.
> 
> The task graph interface can be used describe more
> complicated task dependencies in the future and
> provides the immediate benefit of seamlessly being
> able to cancel and re-prioritize tasks.
> 
> BUG=178974
> 
> Review URL: https://chromiumcodereview.appspot.com/14689004

TBR=reveman@chromium.org

Review URL: https://codereview.chromium.org/16178002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@202736 0039d316-1c4b-4281-b951-d872f2087c98