Reduce buggy usage of the registry controlled domain service.

net/base/registry_controlled_domains/registry_controlled_domain.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // NB: Modelled after Mozilla's code (originally written by Pamela Greene,
 // later modified by others), but almost entirely rewritten for Chrome.
 //   (netwerk/dns/src/nsEffectiveTLDService.h)
 /* ***** BEGIN LICENSE BLOCK *****
  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
  *
@@ skipping 209 matching lines @@
 //                                                         dots)
 //   http://192.168.0.1/file.html    -> 0                 (IP address)
 //   http://bar/file.html            -> 0                 (no subcomponents)
 //   http://co.uk/file.html          -> 0                 (host is a registry)
 //   http://foo.bar/file.html        -> 0 or 3, depending (no rule; assume
 //                                                         bar)
 NET_EXPORT size_t GetRegistryLength(const GURL& gurl,
                                     UnknownRegistryFilter unknown_filter,
                                     PrivateRegistryFilter private_filter);
 
-// Like the GURL version, but takes a host (which is canonicalized internally)
-// instead of a full GURL.
-NET_EXPORT size_t GetRegistryLength(base::StringPiece host,
-                                    UnknownRegistryFilter unknown_filter,
-                                    PrivateRegistryFilter private_filter);
+// Returns true if the given host name has a registry-controlled domain. The
+// nost name will be internally canonicalized. Invalid host names like
+// "*.google.com" can be passed and will return true as long as it has a valid
+// registry-controlled portion.
+NET_EXPORT bool HostHasRegistryControlledDomain(
+    base::StringPiece host,
+    UnknownRegistryFilter unknown_filter,
+    PrivateRegistryFilter private_filter);
+
+// Like GetRegistryLength, but takes a previously-canonicalized host. Prefer
+// the GURL version above or HasRegistryControlledSuffix to eliminate
+// bugs with non-canonical hosts.
+NET_EXPORT size_t
+GetRegistryLengthForCanonicalHost(base::StringPiece canon_host,
+                                  UnknownRegistryFilter unknown_filter,
+                                  PrivateRegistryFilter private_filter);
+
+// This function canonicalizes the host name and returns the registry controlled
+// length of the canonical version.
+//
+// TODO(bug 657199) any use of this length by the caller is likely a bug.
+// Canonicalization can change the length of different URL components, so using
+// the returned value as an index into the returned string will be incorrect. If
+// you have a canonicalized URL, this is safe and you should use
+// GetRegistryLengthForCanonicalHost above.
+NET_EXPORT size_t
+BuggyGetHostRegistryLength(const std::string& host,
+                           UnknownRegistryFilter unknown_filter,
+                           PrivateRegistryFilter private_filter);
 
 typedef const struct DomainRule* (*FindDomainPtr)(const char *, unsigned int);
 
 // Used for unit tests. Use default domains.
 NET_EXPORT_PRIVATE void SetFindDomainGraph();
 
 // Used for unit tests, so that a frozen list of domains is used.
 NET_EXPORT_PRIVATE void SetFindDomainGraph(const unsigned char* domains,
                                            size_t length);
 }  // namespace registry_controlled_domains
 }  // namespace net
 
 #endif  // NET_BASE_REGISTRY_CONTROLLED_DOMAINS_REGISTRY_CONTROLLED_DOMAIN_H_