Content analysis should block all files if one is blocked.

When the user selects more than one file and enterprise content
analysis is turned on, one blocked file should block all files.  This
makes file selection consistent with dragging and dropping of files.

Bug: b:243673304
Change-Id: I142da1cdedc1f69329ace94256395ef3182e4905
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3857878


Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Roger Tawa <rogerta@chromium.org>
Reviewed-by: Dominique Fauteux-Chapleau <domfc@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1040964}