Provide the equivalent of GURL::DomainIs for url::Origin.

url/url_util.h

Index: url/url_util.h
diff --git a/url/url_util.h b/url/url_util.h
index a209a61c76029bed62f70c471e53bbfedd848332..baae84a400fe7ca52c68c3f24112d0f543341d83 100644
--- a/url/url_util.h
+++ b/url/url_util.h
@@ -8,6 +8,7 @@
 #include <string>
 
 #include "base/strings/string16.h"
+#include "base/strings/string_piece.h"
 #include "url/third_party/mozilla/url_parse.h"
 #include "url/url_canon.h"
 #include "url/url_constants.h"
@@ -217,6 +218,16 @@ URL_EXPORT void EncodeURIComponent(const char* input,
                                    int length,
                                    CanonOutput* output);
 
+// Returns true if the |canonicalized_host| matches or is in the same domain as

[engedy, 2016/08/26 16:48:14]

I'd argue this should go into a new section before line 136.

// Domains --

[pkalinnikov, 2016/08/29 09:53:00]

Done.

+// the given |lower_ascii_domain| string. For example, if the canonicalized
+// hostname is "www.google.com", this will return true for "com", "google.com",
+// and "www.google.com" domains.
+//
+// The input domain should be a non-empty lower-case ASCII string to match the
+// canonicalized host. The host should be non-empty as well.
+URL_EXPORT bool DomainIs(base::StringPiece canonicalized_host,
+                         base::StringPiece lower_ascii_domain);
+
 }  // namespace url
 
 #endif  // URL_URL_UTIL_H_