First version of gpuveto testing script

This CL just sketches out the structure of the gpuveto testing process. Two big areas for improvement are:
  render the picture in tiles and label as unsuitable if any gpu tile is slower than raster
  decide on whether tilegrid is used or not

As expected the current gpuveto heuristic isn't so good:

predicted 	   suitable    unsuitable
-------------------------------------------
actual suitable      10           17
actual unsuitable    15           27

R=rmistry@google.com, bsalomon@google.com

Author: robertphillips@google.com

Review URL: https://codereview.chromium.org/257723003

git-svn-id: http://skia.googlecode.com/svn/trunk@14416 2bbb7eff-a529-9590-31e7-b0007b416f81
1 file changed