Supplimentary identifier for passwords specific

components/sync/core_impl/sync_encryption_handler_impl.cc

Index: components/sync/core_impl/sync_encryption_handler_impl.cc
diff --git a/components/sync/core_impl/sync_encryption_handler_impl.cc b/components/sync/core_impl/sync_encryption_handler_impl.cc
index 686abbb45c4fddadeaa1e601fc0682f5b82497da..f5f64cd94ee5b8576735be1550d30729f367fd9f 100644
--- a/components/sync/core_impl/sync_encryption_handler_impl.cc
+++ b/components/sync/core_impl/sync_encryption_handler_impl.cc
@@ -195,6 +195,14 @@ bool UnpackKeystoreBootstrapToken(const std::string& keystore_bootstrap_token,
   return true;
 }
 
+// If the user starts using custom passphrase, then unencrypted metadata fields
+// for the password entity should be cleared.
+sync_pb::PasswordSpecificsMetadata
+ProcessPasswordSpecificMetadataForExplicitPassphareUsers(
+    const sync_pb::PasswordSpecificsMetadata& password_metadata) {
+  return sync_pb::PasswordSpecificsMetadata();
+}
+
 }  // namespace
 
 SyncEncryptionHandlerImpl::Vault::Vault(Encryptor* encryptor,
@@ -842,6 +850,11 @@ void SyncEncryptionHandlerImpl::ReEncryptEverything(WriteTransaction* trans) {
       if (child.InitByIdLookup(child_id) != BaseNode::INIT_OK)
         break;  // Possible if we failed to decrypt the data for some reason.
       child.SetPasswordSpecifics(child.GetPasswordSpecifics());
+      if (IsExplicitPassphrase(passphrase_type_)) {
+        child.SetPasswordSpecificsMetadata(

[Nicolas Zea, 2016/08/20 00:23:43]

It occurs to me that I don't think you need this. SetPasswordSpecifics above
should automatically clear this as necessary (see my comment in write_node.cc).
You'll need to make some changes to nigori_util.cc to make that happen.

[melandory, 2016/08/22 22:08:41]

Disclaimer. Text below is written with an assumption of following setup: 
* data is cleared in nigori_util, UpdateEntryWithEncryption
* in order to get encryption state we query NigoriHandler::GetEncryptedTypes and
if encrypted types equal to EncryptableUserTypes, then it is custom passphrase
user .

So there is one thing which bothers me in proposed approach (or at least about
implementation I described).

Information that if user has custom_passphrase when "encrypt everything" is true
is external to the UpdateEntryWithEncryption and I think currently there is no
tests which check that this hypothesis is always true.

I see several ways to solve this:
1. Pipe passphrase_type_ flag to UpdateEntryWithEncryption.
2. Keep clearing of data in sync_encryption_handler_impl.cc, where we have
explicit signal about passphrase type.
3. Do implementation as written in the paragraph above and try to come up with a
solution for testing that custom passphrase state == encrypt everything state.

WDYT?

+            ProcessPasswordSpecificMetadataForExplicitPassphareUsers(
+                child.GetPasswordSpecificsMetadata()));
+      }
       child_id = child.GetSuccessorId();
     }
   }