Change Observer: Add WPTs for observing files that don't exist
Adds WPTs to test that observe() fails when the file or directory does
not exist.
Bug: 341136316
Change-Id: I9047bbe48fa3c05a07b63e7c7817c4337384c782
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5749999
Auto-Submit: Nathan Memmott memmott@chromium.org
Reviewed-by: Daseul Lee dslee@chromium.org
Commit-Queue: Daseul Lee dslee@chromium.org
Cr-Commit-Position: refs/heads/main@{#1335103}