Add Yandex referral ID to search URL.

components/search_engines/template_url.cc

Index: components/search_engines/template_url.cc
diff --git a/components/search_engines/template_url.cc b/components/search_engines/template_url.cc
index b4fb151639c6799de44dc0008764ebc6a051e3c2..2bb5fe9f0c9cb8e983c0273b743de9ed57b95d20 100644
--- a/components/search_engines/template_url.cc
+++ b/components/search_engines/template_url.cc
@@ -649,6 +649,8 @@ bool TemplateURLRef::ParseParameter(size_t start,
     replacements->push_back(Replacement(GOOGLE_SUGGEST_REQUEST_ID, start));
   } else if (parameter == kGoogleUnescapedSearchTermsParameter) {
     replacements->push_back(Replacement(GOOGLE_UNESCAPED_SEARCH_TERMS, start));
+  } else if (parameter == "yandex:referralID") {
+    replacements->push_back(Replacement(YANDEX_REFERRAL_ID, start));
   } else if (parameter == "yandex:searchPath") {
     switch (ui::GetDeviceFormFactor()) {
       case ui::DEVICE_FORM_FACTOR_DESKTOP:
@@ -1125,6 +1127,18 @@ std::string TemplateURLRef::HandleReplacements(
 #endif
         break;
 
+      case YANDEX_REFERRAL_ID: {
+        DCHECK(!i->is_post_param);

[Peter Kasting, 2017/05/09 00:14:25]

Is this important?  Why?

[Ted C, 2017/05/09 04:38:32]

this and the comment below were blatantly cribbed from RLZ above.  I can remove
both entirely though.

+        // On platforms that don't have Referral ID, we still want this branch
+        // to happen so that we replace the Referral ID template with the
+        // empty string.  (If we don't handle this case, we hit a
+        // NOTREACHED below.)

[Peter Kasting, 2017/05/09 00:14:25]

I'm confused.  Is this referring to having a case for this at all?  If so I'd
just omit this comment, as it seems more confusing than helpful.

+        std::string referral_id = search_terms_data.YandexReferralID();
+        if (!referral_id.empty())
+          HandleReplacement("clid", referral_id, *i, &url);
+        break;
+      }
+
       default:
         NOTREACHED();
         break;