dlp: Merge additional comment on M110 to main

(cherry picked from commit da543cb)

Bug: 1402113
Change-Id: Ie04d5e603c7f0e8f33ad88705187a80fe16e3c5f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4117069
Reviewed-by: Sergey Poromov <poromov@chromium.org>
Commit-Queue: Daniel Brinkers <brinky@google.com>
Cr-Original-Original-Commit-Position: refs/heads/main@{#1085416}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4134065
Auto-Submit: Daniel Brinkers <brinky@google.com>
Reviewed-by: Aya Elsayed <ayaelattar@chromium.org>
Cr-Original-Commit-Position: refs/branch-heads/5481@{#122}
Cr-Original-Branched-From: 130f3e4-refs/heads/main@{#1084008}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4134171
Commit-Queue: Aya Elsayed <ayaelattar@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1090085}

chrome/browser/chromeos/policy/dlp/dlp_copy_or_move_hook_delegate.cc

@@ -42,6 +42,8 @@ void GotAccess(base::WeakPtr<DlpCopyOrMoveHookDelegate> hook_delegate,
         base::BindOnce(&DlpCopyOrMoveHookDelegate::GotAccess, hook_delegate,
                        source, destination, std::move(access)));
   }
+  // The `callback` was bound to the calling thread in OnBeginProcessFile and
+  // will be executed on the IO thread.
   if (is_allowed) {
     std::move(callback).Run(base::File::FILE_OK);
   } else {