Always position floats from fragment->PositionedFloats list.

BUG=635619
TESTS=8 new test failures
All failed tests were investigated and assigned to corresponding bugs.
The main reason why they started failing is because we actually started rendering something instead of producing an empty page.

Review-Url: https://codereview.chromium.org/2885943003
Cr-Commit-Position: refs/heads/master@{#472884}
2 files changed