Disable FedCM functionality

patches/core/ungoogled-chromium/remove-unused-preferences-fields.patch

@@ -6748,3 +6748,37 @@
  // TODO(crbug.com/40904479): Maybe move to chrome_syncable_prefs_database.cc,
  // see bug.
  #if !BUILDFLAG(IS_ANDROID) && !BUILDFLAG(IS_IOS)
+--- a/content/browser/webid/federated_auth_request_impl.cc
++++ b/content/browser/webid/federated_auth_request_impl.cc
+@@ -579,31 +579,6 @@ FederatedAuthRequestImpl::~FederatedAuth
+ void FederatedAuthRequestImpl::Create(
+     RenderFrameHost* host,
+     mojo::PendingReceiver<blink::mojom::FederatedAuthRequest> receiver) {
+-  CHECK(host);
+-
+-  BrowserContext* browser_context = host->GetBrowserContext();
+-  raw_ptr<FederatedIdentityApiPermissionContextDelegate>
+-      api_permission_context =
+-          browser_context->GetFederatedIdentityApiPermissionContext();
+-  raw_ptr<FederatedIdentityAutoReauthnPermissionContextDelegate>
+-      auto_reauthn_permission_context =
+-          browser_context->GetFederatedIdentityAutoReauthnPermissionContext();
+-  raw_ptr<FederatedIdentityPermissionContextDelegate> permission_context =
+-      browser_context->GetFederatedIdentityPermissionContext();
+-  raw_ptr<IdentityRegistry> identity_registry =
+-      IdentityRegistry::FromWebContents(WebContents::FromRenderFrameHost(host));
+-
+-  if (!api_permission_context || !auto_reauthn_permission_context ||
+-      !permission_context) {
+-    return;
+-  }
+-
+-  // FederatedAuthRequestImpl owns itself. It will self-destruct when a mojo
+-  // interface error occurs, the RenderFrameHost is deleted, or the
+-  // RenderFrameHost navigates to a new document.
+-  new FederatedAuthRequestImpl(
+-      *host, api_permission_context, auto_reauthn_permission_context,
+-      permission_context, identity_registry, std::move(receiver));
+ }
+
+ FederatedAuthRequestImpl& FederatedAuthRequestImpl::CreateForTesting(

patches/extra/ungoogled-chromium/remove-uneeded-ui.patch

@@ -23,6 +23,7 @@
 # the feedback entry in the third party cookie popup
 # unneeded elements from the profile menu
 # the 'Learn more' link on crashed tabs
+# the Third-party sign-in site settings (FedCM)
 # disable LiveCaption flag by default, this also removes non-functional Live Caption checkbox from media controls
 # the new feature badges
 
@@ -447,6 +448,17 @@
 
  void SadTabView::OnBoundsChanged(const gfx::Rect& previous_bounds) {
    // Specify the maximum message and title width explicitly.
+--- a/chrome/browser/ui/webui/settings/settings_localized_strings_provider.cc
++++ b/chrome/browser/ui/webui/settings/settings_localized_strings_provider.cc
+@@ -3238,7 +3238,7 @@ void AddSiteSettingsStrings(content::Web
+       base::FeatureList::IsEnabled(blink::features::kWebPrinting));
+
+   html_source->AddBoolean("enableFederatedIdentityApiContentSetting",
+-                          base::FeatureList::IsEnabled(features::kFedCm));
++                          false);
+
+   base::CommandLine& cmd = *base::CommandLine::ForCurrentProcess();
+   html_source->AddBoolean(
 --- a/media/base/media_switches.cc
 +++ b/media/base/media_switches.cc
 @@ -938,7 +938,7 @@ BASE_FEATURE(kOnDeviceWebSpeech,