Revert "Fix border radius on composited children."

This reverts commit https://crrev.com/0cfffd46dfaa1ee93d3d667f82b2fb3721078b34

Chrome's sign-in flow is broken as a result of this patch.
Content inside an element with border-radius is not rendering.

Reverted review URL: https://codereview.chromium.org/2194273002

TBR=chrishtr@chromium.org
BUG=157218,673668,673725
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2569253002
Cr-Commit-Position: refs/heads/master@{#438234}
30 files changed