SameSite: Strict/Lax behavior.

net/base/registry_controlled_domains/registry_controlled_domain.cc

Index: net/base/registry_controlled_domains/registry_controlled_domain.cc
diff --git a/net/base/registry_controlled_domains/registry_controlled_domain.cc b/net/base/registry_controlled_domains/registry_controlled_domain.cc
index 0d98eada13b9c7c700e385c7e30c79560b2a5f34..3c2c95dbcbfcc631a1c58be908e198aa2c111757 100644
--- a/net/base/registry_controlled_domains/registry_controlled_domain.cc
+++ b/net/base/registry_controlled_domains/registry_controlled_domain.cc
@@ -52,6 +52,7 @@
 #include "net/base/net_module.h"
 #include "net/base/url_util.h"
 #include "url/gurl.h"
+#include "url/origin.h"
 #include "url/third_party/mozilla/url_parse.h"
 
 namespace net {
@@ -215,6 +216,16 @@ bool SameDomainOrHost(
                   host1.len);
 }
 
+bool SameDomainOrHost(const url::Origin& origin1,
+                      const url::Origin& origin2,
+                      PrivateRegistryFilter filter) {
+  if (origin1.unique() || origin2.unique())

[mmenke, 2016/03/17 19:15:56]

Why doesn't SameDomainOrHost need this check?  Also, is this check tested?

[Mike West, 2016/03/17 19:57:12]

This is leftover from a previous version; we don't need this check (as unique
origins serialize to "null", which is an invalid GURL, which means that the GURL
version will return `false`).

+    return false;
+
+  return SameDomainOrHost(GURL(origin1.Serialize()), GURL(origin2.Serialize()),
+                          filter);

[mmenke, 2016/03/17 19:15:56]

This seems backwards.  Really seems like SameDomainOrHost(gurl1, gurl2) should
just be calling SameDomainOrHost(gurl1.GetOrigin(), gurl2.GetOrigin());

[Mike West, 2016/03/17 19:57:12]

I thought about that, but we'd need to add some infrastructure to `url::Origin`.
In particular, `SameDomainOrHost` relies on `GetDomainOrRegistry`, which calls
out to `GURL::HostIsIPAddress`. That relies on some URL parsing infrastructure
that assumes it has a whole URL, and relies on canonicalizing the host
`url::Component`. It turned into a whole lot of code for something that's a lot
simpler to handle by going from an `url::Origin` to `GURL`.

I can go that route if you think it's worthwhile, but it will take a CL or three
to get through.

[mmenke, 2016/03/18 15:58:12]

Didn't respond to this, but I think it's fine for now.  Longer term, may be
worth doing, though.

+}
+
 size_t GetRegistryLength(
     const GURL& gurl,
     UnknownRegistryFilter unknown_filter,