Convert AutofillAutomationTestCase to new JSONReader API

Update the implementation of AutofillAutomationTestCase to
use JSONReader::Read instead of JSONReader::ReadDeprecated.

Bug: 925165
Change-Id: I6048349675225b82f04274b209064d258ef02ac2
Reviewed-on: https://chromium-review.googlesource.com/c/1477226
Auto-Submit: Sylvain Defresne <sdefresne@chromium.org>
Commit-Queue: Moe Ahmadi <mahmadi@chromium.org>
Reviewed-by: Moe Ahmadi <mahmadi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#633713}
1 file changed