Enable per-tile logging in bench_pictures

- Modify bench_pictures buildstep to translate "key: True" --> "--key" rather
  than requiring "key: value" --> "--key value"
- Add whacky TileArgs helper which includes "timeIndividualTiles: True"
Review URL: https://codereview.appspot.com/7092046

git-svn-id: http://skia.googlecode.com/svn/trunk@7141 2bbb7eff-a529-9590-31e7-b0007b416f81
2 files changed