Moved --use-gl=osmesa to UITest::SetUp so it is not visible to pyautolib.
Moved --use-gl=osmesa to UITest::SetUp so it is not visible to pyautolib.

It derives from UITestBase.

TEST=ui_tests
BUG=62602

Review URL: http://codereview.chromium.org/4662005

git-svn-id: http://src.chromium.org/svn/trunk/src@65616 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 70f9d21b262a462d05a7c45dc0d1a985ee9be6dd
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