Force enable Shadow DOM v0 for chrome driver.

This patch is a preparation for Shadow DOM V0, Custom Element V0 (CEv0) and HTML Imports removal.
Intent to Deprecate and Remove:
Though we soon make these APIs only available for test by turning the json5 feature flag
from status: "stable" to status: "test", there is browser tests/chrome internal components that
use them.

ChromeDriverTest is a one of them and this patch reenable Shadow DOM v0 for it.
We should migration it using new APIs.

Bug: 911943
Change-Id: I0d97f4414aa5d17ddd611a38f34c34238880e27e
Reviewed-by: John Chen <>
Commit-Queue: Yoichi Osato <>
Cr-Commit-Position: refs/heads/master@{#622281}
1 file changed