Add base::FeatureParam<> struct

components/ntp_snippets/remote/remote_suggestions_fetcher.cc

Index: components/ntp_snippets/remote/remote_suggestions_fetcher.cc
diff --git a/components/ntp_snippets/remote/remote_suggestions_fetcher.cc b/components/ntp_snippets/remote/remote_suggestions_fetcher.cc
index 183519908a093eb73a983e93c68132d7be56050d..110b9610b846bd639daaa8d40e1ecac886f6d6e5 100644
--- a/components/ntp_snippets/remote/remote_suggestions_fetcher.cc
+++ b/components/ntp_snippets/remote/remote_suggestions_fetcher.cc
@@ -15,13 +15,13 @@ namespace ntp_snippets {
 namespace {
 
 // Variation parameter for chrome-content-suggestions backend.
-const char kContentSuggestionsBackend[] = "content_suggestions_backend";
+constexpr base::FeatureParam<std::string> kContentSuggestionsBackend{
+    &kArticleSuggestionsFeature, "content_suggestions_backend", ""};
 
 }  // namespace
 
 GURL GetFetchEndpoint(version_info::Channel channel) {
-  std::string endpoint = variations::GetVariationParamValueByFeature(
-      ntp_snippets::kArticleSuggestionsFeature, kContentSuggestionsBackend);
+  std::string endpoint = kContentSuggestionsBackend.Get();
   if (!endpoint.empty()) {
     return GURL{endpoint};
   }