Commits on Dec 17, 2015

1. Add test to constellation to avoid writing reftest image if there are… …

   … pending frames.
   
   Also change when pipelines become active.
   
   This makes the constellation activate a pipeline as the current frame
   when it is ready to do initial reflow, rather than when it is ready
   to paint.
   
   This fixes a number of intermittent failures that could previously occur
   if an iframe was not visible - which would mean it was never moved from
   a pending frame in the constellation to an active frame.
   
   (It happens that webrender exposes these intermittents as permanent failures).

   

   gw3583 committed Dec 17, 2015

   Loading status checks…
   b670430