[autofill] Add support for PSL domain matching for password autofill.

content/public/common/password_form.h

Index: content/public/common/password_form.h
diff --git a/content/public/common/password_form.h b/content/public/common/password_form.h
index 1a70685305b274874b49720e53a4f68c73aa6b28..4fced39c219c25d839ad3262ac9b3d5d056a1c3c 100644
--- a/content/public/common/password_form.h
+++ b/content/public/common/password_form.h
@@ -54,6 +54,24 @@ struct CONTENT_EXPORT PasswordForm {
   // data from the database, so it must not be empty.
   std::string signon_realm;
 
+  // The original "Realm" for the sign-on (scheme, host, port for SCHEME_HTML,
+  // and contains the HTTP realm for dialog-based forms). This realm is only set
+  // when two PasswordForms are matched when trying to find a login/pass pair
+  // for a site. It is only set to a non-empty value during a match of the
+  // original stored login/pass and the current observed form if all these
+  // statements are true:
+  // 1) The full signon_realm is not the same.
+  // 2) The registry controlled domain is the same. For example; example.com,
+  // m.example.com, foo.login.example.com and www.example.com would all resolve
+  // to example.com since .com is the public suffix.
+  // 3) The scheme is the same.
+  // 4) The port is the same.
+  // For example, if there exists a stored password for http://www.example.com
+  // (where .com is the public suffix) and the observed form is
+  // http://m.example.com, |original_signon_realm| must be set to
+  // http://www.example.com.
+  std::string original_signon_realm;
+
   // The URL (minus query parameters) containing the form. This is the primary
   // data used by the PasswordManager to decide (in longest matching prefix
   // fashion) whether or not a given PasswordForm result from the database is a
@@ -163,6 +181,9 @@ struct CONTENT_EXPORT PasswordForm {
   // When parsing an HTML form, this is not used.
   int times_used;
 
+  // Returns true if this match was found using public suffix matching.
+  bool IsPublicSuffixMatch() const;
+
   PasswordForm();
   ~PasswordForm();
 };