[AiS] Provide Answers queries with a session token.

chrome/browser/search_engines/template_url.h

Index: chrome/browser/search_engines/template_url.h
diff --git a/chrome/browser/search_engines/template_url.h b/chrome/browser/search_engines/template_url.h
index 9d0435593268b94173aaef96ddecf902347b1273..67f27cacea1cc0e39eaa7ab49d562489c9c2ea45 100644
--- a/chrome/browser/search_engines/template_url.h
+++ b/chrome/browser/search_engines/template_url.h
@@ -105,6 +105,9 @@ class TemplateURLRef {
     // True for searches issued with the bookmark bar pref set to shown.
     bool bookmark_bar_pinned;
 
+    // Optional session token.
+    std::string session_token;
+
     // Additional query params provided by the suggest server.
     std::string suggest_query_params;
 
@@ -273,6 +276,7 @@ class TemplateURLRef {
     GOOGLE_RLZ,
     GOOGLE_SEARCH_CLIENT,
     GOOGLE_SEARCH_FIELDTRIAL_GROUP,
+    GOOGLE_SESSION_TOKEN,
     GOOGLE_SUGGEST_CLIENT,
     GOOGLE_SUGGEST_REQUEST_ID,
     GOOGLE_UNESCAPED_SEARCH_TERMS,