Modifying the behavior of render_pictures --validate to test the effect of bbh.

The new behavior consists in using the same renderer, with bbh disabled, as a reference
renderer when the current renderer has a bbh.
Review URL: https://codereview.chromium.org/12801002

git-svn-id: http://skia.googlecode.com/svn/trunk@8132 2bbb7eff-a529-9590-31e7-b0007b416f81
2 files changed