Commits on Nov 20, 2015

1. Implement binning for the texture cache and a couple more improvements. …

   * Sort texture cache items into bins in order to minimize the free list
     scan time.
   
   * Improve the texture cache API by switching the "alternate" Boolean to
     an enum.
   
   * Store texture sizes in cache items. This will be useful when we switch
     render targets to be allocated out of the texture cache.
   
   * When coalescing rects, don't eagerly iterate to a fixed point. Instead
     just do as many iterations as we need to satisfy the request.

   

   pcwalton committed Nov 20, 2015
   b252d0f