Make CreateUnsafeCookieForTesting return a unique_ptr.

This will make it easier to use this factory when testing code that uses
SetCanonicalCookie() and other methods that take unique_ptrs to
CanonicalCookies.

The factory method uses base::WrapUnique to create the unique_ptr so
that the constructor can be made private. I plan on updating the other
factory methods to use base::WrapUnique instead of make_unique in a
follow-up CL.

Bug: 1102874
Change-Id: I3e84fbc68ce95438a5adfdac46573df9efe4e38d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2559311Reviewed-by: Maksim Orlovich <morlovich@chromium.org>
Commit-Queue: Dylan Cutler <dylancutler@google.com>
Cr-Commit-Position: refs/heads/master@{#831072}

net/cookies/canonical_cookie.cc

@@ -50,6 +50,7 @@
 #include "base/feature_list.h"
 #include "base/format_macros.h"
 #include "base/logging.h"
+#include "base/memory/ptr_util.h"
 #include "base/metrics/histogram_functions.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/strings/strcat.h"
@@ -553,7 +554,7 @@ std::unique_ptr<CanonicalCookie> CanonicalCookie::FromStorage(
 }
 
 // static
-CanonicalCookie CanonicalCookie::CreateUnsafeCookieForTesting(
+std::unique_ptr<CanonicalCookie> CanonicalCookie::CreateUnsafeCookieForTesting(
     const std::string& name,
     const std::string& value,
     const std::string& domain,
@@ -568,9 +569,9 @@ CanonicalCookie CanonicalCookie::CreateUnsafeCookieForTesting(
     bool same_party,
     CookieSourceScheme source_scheme,
     int source_port) {
-  return CanonicalCookie(name, value, domain, path, creation, expiration,
-                         last_access, secure, httponly, same_site, priority,
-                         same_party, source_scheme, source_port);
+  return base::WrapUnique(new CanonicalCookie(
+      name, value, domain, path, creation, expiration, last_access, secure,
+      httponly, same_site, priority, same_party, source_scheme, source_port));
 }
 
 std::string CanonicalCookie::DomainWithoutDot() const {

net/cookies/canonical_cookie.h

@@ -147,7 +147,7 @@ class NET_EXPORT CanonicalCookie {
 
   // Create a CanonicalCookie that is not guaranteed to actually be Canonical
   // for tests. This factory should NOT be used in production.
-  static CanonicalCookie CreateUnsafeCookieForTesting(
+  static std::unique_ptr<CanonicalCookie> CreateUnsafeCookieForTesting(
       const std::string& name,
       const std::string& value,
       const std::string& domain,