Use getAttribute in path animation tests

Use getAttribute('d') and exact string matching instead of using
animatedPathSegList. The base value checks are dropped. In some cases
relative close commands ('z') are replaced with absolute ones ('Z').

BUG=539385

Review URL: https://codereview.chromium.org/1417593003

Cr-Commit-Position: refs/heads/master@{#355119}
16 files changed