SameSite: Implement 'Strict'/'Lax' attribute parsing.

ios/net/cookies/cookie_cache_unittest.cc

Index: ios/net/cookies/cookie_cache_unittest.cc
diff --git a/ios/net/cookies/cookie_cache_unittest.cc b/ios/net/cookies/cookie_cache_unittest.cc
index 3aba46d56002bdeb0aa319ec34d2c9951f2e21c9..188d0bcb5a82b10cdd7331bebd3542998fad3cea 100644
--- a/ios/net/cookies/cookie_cache_unittest.cc
+++ b/ios/net/cookies/cookie_cache_unittest.cc
@@ -18,7 +18,8 @@ CanonicalCookie MakeCookie(const GURL& url,
                            const std::string& name,
                            const std::string& value) {
   return CanonicalCookie(url, name, value, url.host(), url.path(), base::Time(),
-                         base::Time(), base::Time(), false, false, false,
+                         base::Time(), base::Time(), false, false,
+                         net::CookieSameSite::DEFAULT_MODE,
                          net::COOKIE_PRIORITY_DEFAULT);
 }