GitLab

This rounds out my patch series to point image decoding benchmark at
image_decoding_benchmark.json but also get a tough_image_cases pageset
established.

NOTRY=True

Review URL: https://chromiumcodereview.appspot.com/11783086

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@176139 0039d316-1c4b-4281-b951-d872f2087c98