Top-align table cells in rows that cross fragmentainer boundaries.

Ignore whatever vertical-align says and force everything to be top aligned in
those cases. Edge also behaves like this.

Doing both fragmentation and vertical alignment for table parts could cause
unresolvable situations (cyclic dependencies).

Two tests that depended on vertical alignment working under such circumstances
are now invalid, and were therefore removed.

BUG=534751

Review-Url: https://codereview.chromium.org/2412923002
Cr-Commit-Position: refs/heads/master@{#425112}
12 files changed