spanification: Add #pragma allow_unsafe_buffers to component/*

See `//docs/unsafe_buffers.md`

This is a preparation to fix each files.
This CL has no behavior changes.

This patch was fully automated using script:
https://paste.googleplex.com/5614491201175552

See internal doc about it:
https://docs.google.com/document/d/1erdcokeh6rfBqs_h0drHqSLtbDbB61j7j3O2Pz8NH78/edit?resourcekey=0-hNe6w1hYAYyVXGEpWI7HVA&tab=t.0

AX-Relnotes: n/a.
Bug: 40285824
Change-Id: I24ff0aee7a6cbe6da11a08830135449ccf8f2ae2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5717711
Commit-Queue: Arthur Sonzogni <arthursonzogni@chromium.org>
Auto-Submit: Arthur Sonzogni <arthursonzogni@chromium.org>
Reviewed-by: Cait Phillips <caitkp@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1335315}

components/safe_search_api/safe_search/safe_search_url_checker_client_unittest.cc

@@ -2,6 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#ifdef UNSAFE_BUFFERS_BUILD
+// TODO(crbug.com/40285824): Remove this and convert code to safer constructs.
+#pragma allow_unsafe_buffers
+#endif
+
 #include "components/safe_search_api/safe_search/safe_search_url_checker_client.h"
 
 #include <memory>

components/safe_search_api/url_checker_unittest.cc

@@ -2,6 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#ifdef UNSAFE_BUFFERS_BUILD
+// TODO(crbug.com/40285824): Remove this and convert code to safer constructs.
+#pragma allow_unsafe_buffers
+#endif
+
 #include "components/safe_search_api/url_checker.h"
 
 #include <stddef.h>