GTTF: Make it possible to run ui_tests in parallel by making each browser instance log to its own log file.
GTTF: Make it possible to run ui_tests in parallel by making each browser instance
log to its own log file.

Otherwise each launched browser would overwrite the shared log. The test infrastructure
relies on the log file to detect assertion failures.

BUG=54098
TEST=none

Review URL: http://codereview.chromium.org/3405025

git-svn-id: http://src.chromium.org/svn/trunk/src@60441 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 2f0fa40b3d117e9537841314333e26d822315974
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser