Alter bench_pictures to "respect" the logPerIter flag.

Alter bench_pictures to "respect" the logPerIter flag.

When --logPerIters is set and --repeat is great then 2 then bench_pictures will run each test "repeat" times (to generate the correct number of timings) by rendering 5 times.

This CL also adds a swapBuffers in addition to the pre-existing flush calls.

R=bsalomon@google.com

Author: robertphillips@google.com

Review URL: https://codereview.chromium.org/194973003

git-svn-id: http://skia.googlecode.com/svn/trunk@13752 2bbb7eff-a529-9590-31e7-b0007b416f81