[cr149] SetCanonicalCookieAsync dropping default arg value

This is just a mirror of the change in upstream.

Chromium changes:
https://chromium.googlesource.com/chromium/src/+/4d84d8a0cdb1b946de455ec1f511c7205f9b27ab

commit 4d84d8a0cdb1b946de455ec1f511c7205f9b27ab
Author: Chris Fredrickson <cfredric@chromium.org>
Date:   Mon Apr 13 02:15:19 2026 -0700

    Remove default args from CookieStore virtual methods

    Virtual methods are forbidden to have default arguments by the style
    guide
    (https://google.github.io/styleguide/cppguide.html#Default_Arguments).

    Change-Id: I42528f3dd0aa2750cd6a1d773e53f6f4d5fc3891
    Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7726975
    Reviewed-by: Joey Arhar <jarhar@chromium.org>
    Auto-Submit: Chris Fredrickson <cfredric@chromium.org>
    Reviewed-by: Rohit Rao <rohitrao@chromium.org>
    Commit-Queue: Victor Vianna <victorvianna@google.com>
    Reviewed-by: Richard (Torne) Coles <torne@chromium.org>
    Reviewed-by: Victor Vianna <victorvianna@google.com>
    Cr-Commit-Position: refs/heads/main@{#1613572}

chromium_src/net/cookies/cookie_monster.h

@@ -44,8 +44,7 @@ class NET_EXPORT CookieMonster : public chromium_impl::CookieMonster {
       const GURL& source_url,
       const CookieOptions& options,
       SetCookiesCallback callback,
-      std::optional<CookieAccessResult> cookie_access_result =
-          std::nullopt) override;
+      std::optional<CookieAccessResult> cookie_access_result) override;
   void GetCookieListWithOptionsAsync(
       const GURL& url,
       const CookieOptions& options,