Remove LatencyInfo merge from software rendering path

BUG=246034
TEST=unittests pass.

Review URL: https://codereview.chromium.org/111483003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242404 0039d316-1c4b-4281-b951-d872f2087c98
18 files changed