The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/95868e7bb69e4c5cfb90e7c6ea571c351b96f626

commit 95868e7bb69e4c5cfb90e7c6ea571c351b96f626
Author: gangwu <gangwu@chromium.org>
Date: Wed Jun 08 01:54:35 2016

This is 1 of 2 checks in for making ModelTypeStore supports
multiple datatypes.
This one will add ModelType's toor tag as a prefix for keys
in leveldb.
Next check in will make only one ModelTypeStore to be created
if there are multiple datatypes.

BUG= 615214 

Review-Url: https://codereview.chromium.org/2018623002
Cr-Commit-Position: refs/heads/master@{#398457}

[modify] https://crrev.com/95868e7bb69e4c5cfb90e7c6ea571c351b96f626/components/browser_sync/browser/profile_sync_service.cc
[modify] https://crrev.com/95868e7bb69e4c5cfb90e7c6ea571c351b96f626/sync/api/model_type_store.cc
[modify] https://crrev.com/95868e7bb69e4c5cfb90e7c6ea571c351b96f626/sync/api/model_type_store.h
[modify] https://crrev.com/95868e7bb69e4c5cfb90e7c6ea571c351b96f626/sync/internal_api/model_type_store_impl.cc
[modify] https://crrev.com/95868e7bb69e4c5cfb90e7c6ea571c351b96f626/sync/internal_api/public/base/model_type.h
[modify] https://crrev.com/95868e7bb69e4c5cfb90e7c6ea571c351b96f626/sync/internal_api/public/model_type_store_impl.h
[modify] https://crrev.com/95868e7bb69e4c5cfb90e7c6ea571c351b96f626/sync/syncable/model_type.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/71bdb554039faa51622aa87ebdb3b7eeae2dedf0

commit 71bdb554039faa51622aa87ebdb3b7eeae2dedf0
Author: gangwu <gangwu@chromium.org>
Date: Wed Jul 06 22:35:26 2016

This is 2 of 2 checks in for making ModelTypeStore supports
multiple datatypes.

This check-in let ModelTypeStoreBackend can be shared with
multiple ModelTypeStore.

BUG= 615214 

Review-Url: https://codereview.chromium.org/2077713002
Cr-Commit-Position: refs/heads/master@{#403962}

[modify] https://crrev.com/71bdb554039faa51622aa87ebdb3b7eeae2dedf0/sync/internal_api/model_type_store_backend.cc
[modify] https://crrev.com/71bdb554039faa51622aa87ebdb3b7eeae2dedf0/sync/internal_api/model_type_store_backend_unittest.cc
[modify] https://crrev.com/71bdb554039faa51622aa87ebdb3b7eeae2dedf0/sync/internal_api/model_type_store_impl.cc
[modify] https://crrev.com/71bdb554039faa51622aa87ebdb3b7eeae2dedf0/sync/internal_api/public/base/model_type.h
[modify] https://crrev.com/71bdb554039faa51622aa87ebdb3b7eeae2dedf0/sync/internal_api/public/model_type_store_backend.h
[modify] https://crrev.com/71bdb554039faa51622aa87ebdb3b7eeae2dedf0/sync/internal_api/public/model_type_store_impl.h
[modify] https://crrev.com/71bdb554039faa51622aa87ebdb3b7eeae2dedf0/sync/syncable/model_type.cc