[cr145][iOS] PrimaryAccountAccessTokenFetcher c'tor removed.

C'tor versions that take a string have been removed.

Chromium change:

https://source.chromium.org/chromium/chromium/src/+/729bb5f8da429482dfda293fbaeb12c12e5e3852

commit 729bb5f8da429482dfda293fbaeb12c12e5e3852
Author: Tanmoy Mollik <triploblastic@google.com>
Date:   Thu Dec 11 03:16:10 2025 -0800

    Remove unused methods in PrimaryAccountAccessTokenFetcher

    The clients that use oauth_consumer_name constructors of this class have
    been migrated.

    Bug: 425896213

ios/browser/ui/webui/sanitized_image_source.mm

@@ -221,8 +221,7 @@ void SanitizedImageSource::StartDataRequest(
 
   // Request an auth token for downloading the image body.
   auto fetcher = std::make_unique<signin::PrimaryAccountAccessTokenFetcher>(
-      "sanitized_image_source", identity_manager_,
-      signin::ScopeSet({GaiaConstants::kPhotosModuleImageOAuth2Scope}),
+      signin::OAuthConsumerId::kSanitizedImageSource, identity_manager_,
       signin::PrimaryAccountAccessTokenFetcher::Mode::kImmediate,
       signin::ConsentLevel::kSignin);
   auto* fetcher_ptr = fetcher.get();