[Sync] The cryptographer should be able to handle empty or old nigori nodes.

This includes never unsetting the encryption status of a type once it has been
set.

BUG=104218
TEST=unit_tests


Review URL: http://codereview.chromium.org/8564032

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@110578 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/sync/util/cryptographer.cc

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <algorithm>
+
 #include "base/base64.h"
 #include "chrome/browser/sync/util/cryptographer.h"
 #include "chrome/browser/password_manager/encryptor.h"
@@ -326,7 +328,7 @@ void Cryptographer::UpdateEncryptedTypesFromNigori(
     return;
   }
 
-  SetEncryptedTypes(encrypted_types);
+  MergeEncryptedTypes(encrypted_types);
 }
 
 void Cryptographer::UpdateNigoriFromEncryptedTypes(
@@ -376,14 +378,15 @@ syncable::ModelTypeSet Cryptographer::GetEncryptedTypes() const {
   return encrypted_types_;
 }
 
-void Cryptographer::SetEncryptedTypesForTest(
+void Cryptographer::MergeEncryptedTypesForTest(
     const syncable::ModelTypeSet& encrypted_types) {
-  SetEncryptedTypes(encrypted_types);
+  MergeEncryptedTypes(encrypted_types);
 }
 
-void Cryptographer::SetEncryptedTypes(
+void Cryptographer::MergeEncryptedTypes(
     const syncable::ModelTypeSet& encrypted_types) {
-  if (encrypted_types_ == encrypted_types) {
+  if (std::includes(encrypted_types_.begin(), encrypted_types_.end(),
+                    encrypted_types.begin(), encrypted_types.end())) {
     return;
   }
   encrypted_types_ = encrypted_types;

chrome/browser/sync/util/cryptographer.h

@@ -182,17 +182,17 @@ class Cryptographer {
   // Return the set of encrypted types.
   syncable::ModelTypeSet GetEncryptedTypes() const;
 
-  // Forwards to SetEncryptedTypes.
-  void SetEncryptedTypesForTest(
+  // Forwards to MergeEncryptedTypes.
+  void MergeEncryptedTypesForTest(
       const syncable::ModelTypeSet& encrypted_types);
 
  private:
   FRIEND_TEST_ALL_PREFIXES(CryptographerTest, PackUnpack);
   typedef std::map<std::string, linked_ptr<const Nigori> > NigoriMap;
 
-  // Changes the set of encrypted types and emits a notification if
-  // necessary.
-  void SetEncryptedTypes(const syncable::ModelTypeSet& encrypted_types);
+  // Merges the given set of encrypted types with the existing set and emits a
+  // notification if necessary.
+  void MergeEncryptedTypes(const syncable::ModelTypeSet& encrypted_types);
 
   void EmitEncryptedTypesChangedNotification();
 

chrome/browser/sync/util/cryptographer_unittest.cc

@@ -207,7 +207,7 @@ TEST(CryptographerTest, NigoriEncryptionTypes) {
   // Just set the sensitive types (shouldn't trigger any
   // notifications).
   ModelTypeSet encrypted_types(Cryptographer::SensitiveTypes());
-  cryptographer.SetEncryptedTypesForTest(encrypted_types);
+  cryptographer.MergeEncryptedTypesForTest(encrypted_types);
   cryptographer.UpdateNigoriFromEncryptedTypes(&nigori);
   cryptographer2.UpdateEncryptedTypesFromNigori(nigori);
   EXPECT_EQ(encrypted_types, cryptographer.GetEncryptedTypes());
@@ -225,11 +225,18 @@ TEST(CryptographerTest, NigoriEncryptionTypes) {
 
   // Set all encrypted types
   encrypted_types = syncable::GetAllRealModelTypes();
-  cryptographer.SetEncryptedTypesForTest(encrypted_types);
+  cryptographer.MergeEncryptedTypesForTest(encrypted_types);
   cryptographer.UpdateNigoriFromEncryptedTypes(&nigori);
   cryptographer2.UpdateEncryptedTypesFromNigori(nigori);
   EXPECT_EQ(encrypted_types, cryptographer.GetEncryptedTypes());
   EXPECT_EQ(encrypted_types, cryptographer2.GetEncryptedTypes());
+
+   // Receiving an empty nigori should not reset any encrypted types or trigger
+   // an observer notification.
+   Mock::VerifyAndClearExpectations(&observer);
+   nigori = sync_pb::NigoriSpecifics();
+   cryptographer.UpdateEncryptedTypesFromNigori(nigori);
+   EXPECT_EQ(encrypted_types, cryptographer.GetEncryptedTypes());
 }
 
 TEST(CryptographerTest, EncryptEverythingExplicit) {