Add Japan-gated custom logo (#11161)

src/view/icons/useLogoVariant.ts

@@ -0,0 +1,20 @@
+import {useKawaiiMode} from '#/state/preferences/kawaii'
+import {useAnalytics} from '#/analytics'
+import {useGeolocation} from '#/geolocation'
+
+export type LogoVariant = 'default' | 'japan' | 'kawaii'
+
+export function useLogoVariant(allowVariants = true): LogoVariant {
+  const ax = useAnalytics()
+  const geolocation = useGeolocation()
+  const kawaii = useKawaiiMode()
+  const japanLogoEnabled =
+    allowVariants &&
+    geolocation.countryCode === 'JP' &&
+    ax.features.enabled(ax.features.CustomLogoJapanEnable)
+
+  if (!allowVariants) return 'default'
+  if (japanLogoEnabled) return 'japan'
+  if (kawaii) return 'kawaii'
+  return 'default'
+}