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For historical reasons, older tests are written using the js-test harness.
This harness is deprecated, and should not be used for new tests. So, rewrite
The layout test as following new tests guide[1].

[1] https://chromium.googlesource.com/chromium/src/+/master/docs/testing/writing_layout_tests.md#The-js_test_js-Legacy-Harness

BUG=678023

Review-Url: https://codereview.chromium.org/2611713002
Cr-Commit-Position: refs/heads/master@{#441405}