Get ChromeOS browser tests to build when CanonicalCookie's constructor is private.

This is part of a larger effort to make CanonicalCookie's generic
constructor private.

This CL replaces uses of the constructor with the factory
CreateUnsafeCookieForTesting. This factory is meant for test-only code
and should not be used in production.

Make CanonicalCookie's constructor private.

Bug: 1102874
Change-Id: I124942d0aea21cc26a9ee36f35032bde3cb6fba6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2595450Reviewed-by: Maksim Orlovich <morlovich@chromium.org>
Reviewed-by: Roman Sorokin [CET] <rsorokin@chromium.org>
Commit-Queue: Dylan Cutler <dylancutler@google.com>
Cr-Commit-Position: refs/heads/master@{#839660}

chrome/browser/chromeos/login/webview_login_browsertest.cc

@@ -135,14 +135,15 @@ void InjectCookie(content::StoragePartition* storage_partition) {
   storage_partition->GetNetworkContext()->GetCookieManager(
       cookie_manager.BindNewPipeAndPassReceiver());
 
-  net::CanonicalCookie cookie(
-      kTestCookieName, kTestCookieValue, kTestCookieHost, "/", base::Time(),
-      base::Time(), base::Time(), true /* secure */, false /* httponly*/,
-      net::CookieSameSite::NO_RESTRICTION, net::COOKIE_PRIORITY_MEDIUM,
-      false /* same_party */);
+  std::unique_ptr<net::CanonicalCookie> cookie =
+      net::CanonicalCookie::CreateUnsafeCookieForTesting(
+          kTestCookieName, kTestCookieValue, kTestCookieHost, "/", base::Time(),
+          base::Time(), base::Time(), true /* secure */, false /* httponly*/,
+          net::CookieSameSite::NO_RESTRICTION, net::COOKIE_PRIORITY_MEDIUM,
+          false /* same_party */);
   base::RunLoop run_loop;
   cookie_manager->SetCanonicalCookie(
-      cookie, net::cookie_util::SimulatedCookieSource(cookie, "https"),
+      *cookie, net::cookie_util::SimulatedCookieSource(*cookie, "https"),
       net::CookieOptions(),
       base::BindOnce(&InjectCookieDoneCallback, run_loop.QuitClosure()));
   run_loop.Run();