DebugVisualizers: Fix base::Optional

r531722 (crrev.com/c/883946) renamed `is_null_` to `is_populated_`.
This patch fixes chrome.nativs to match to the new name.

Change-Id: Ief8bb4faf90b94a6ca1a4dbd61a5f37bce37273b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1584519
Auto-Submit: Koji Ishii <kojii@chromium.org>
Commit-Queue: Bruce Dawson <brucedawson@chromium.org>
Reviewed-by: Bruce Dawson <brucedawson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#654110}
1 file changed