[SyncFS] Migrate version management from MDDB to index classes

[SyncFS] Migrate version management from MDDB to index classes.

BUG=347425
TEST=./unit_tests --gtest_filter="MetadataDatabase*"

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=283705

[peria, 2014-07-16 04:03:38]

Would you take a look?

[nhiroki, 2014-07-16 04:14:49]

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
File chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc
(right):

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc:24: void
WriteVersionInfo(int64 version, leveldb::WriteBatch* batch) {
PutVersionInfoToBatch(...) ?

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
File
chrome/browser/sync_file_system/drive_backend/metadata_database_index_on_disk.cc
(right):

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
chrome/browser/sync_file_system/drive_backend/metadata_database_index_on_disk.cc:160:
MetadataDatabaseIndexOnDisk::CreateForTesting(leveldb::DB* db) {
How about like this?

1) Making Create() and WriteVersionInfo() accept 'null' batch.
2) Dropping CreateForTesting().
3) Calling Create() in the test.

[peria, 2014-07-16 04:26:08]

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
File chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc
(right):

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc:24: void
WriteVersionInfo(int64 version, leveldb::WriteBatch* batch) {
On 2014/07/16 04:14:48, nhiroki wrote:
> PutVersionInfoToBatch(...) ?

Done.

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
File
chrome/browser/sync_file_system/drive_backend/metadata_database_index_on_disk.cc
(right):

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
chrome/browser/sync_file_system/drive_backend/metadata_database_index_on_disk.cc:160:
MetadataDatabaseIndexOnDisk::CreateForTesting(leveldb::DB* db) {
On 2014/07/16 04:14:49, nhiroki wrote:
> How about like this?
> 
> 1) Making Create() and WriteVersionInfo() accept 'null' batch.
> 2) Dropping CreateForTesting().
> 3) Calling Create() in the test.

Good suggestion.
Done.

[tzik, 2014-07-16 04:35:27]

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
File chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc
(right):

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc:24: void
WriteVersionInfo(int64 version, leveldb::WriteBatch* batch) {
On 2014/07/16 04:14:48, nhiroki wrote:
> PutVersionInfoToBatch(...) ?

Can this be just PutVersionToBatch?

https://codereview.chromium.org/393953010/diff/2/chrome/browser/sync_file_sys...
File chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc
(right):

https://codereview.chromium.org/393953010/diff/2/chrome/browser/sync_file_sys...
chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc:25:
DCHECK(batch);
if (!batch)return; for consistency?

[peria, 2014-07-16 04:40:49]

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
File chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc
(right):

https://codereview.chromium.org/393953010/diff/1/chrome/browser/sync_file_sys...
chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc:24: void
WriteVersionInfo(int64 version, leveldb::WriteBatch* batch) {
On 2014/07/16 04:35:27, tzik wrote:
> On 2014/07/16 04:14:48, nhiroki wrote:
> > PutVersionInfoToBatch(...) ?
> 
> Can this be just PutVersionToBatch?

Done.

https://codereview.chromium.org/393953010/diff/2/chrome/browser/sync_file_sys...
File chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc
(right):

https://codereview.chromium.org/393953010/diff/2/chrome/browser/sync_file_sys...
chrome/browser/sync_file_system/drive_backend/drive_backend_util.cc:25:
DCHECK(batch);
On 2014/07/16 04:35:27, tzik wrote:
> if (!batch)return; for consistency?

Done.

[tzik, 2014-07-16 04:52:25]

lgtm

https://codereview.chromium.org/393953010/diff/30001/chrome/browser/sync_file...
File
chrome/browser/sync_file_system/drive_backend/metadata_database_index_on_disk.cc
(right):

https://codereview.chromium.org/393953010/diff/30001/chrome/browser/sync_file...
chrome/browser/sync_file_system/drive_backend/metadata_database_index_on_disk.cc:151:
if (batch)
can we remove this check?

[nhiroki, 2014-07-16 04:55:25]

lgtm

[peria, 2014-07-16 04:56:45]

https://codereview.chromium.org/393953010/diff/30001/chrome/browser/sync_file...
File
chrome/browser/sync_file_system/drive_backend/metadata_database_index_on_disk.cc
(right):

https://codereview.chromium.org/393953010/diff/30001/chrome/browser/sync_file...
chrome/browser/sync_file_system/drive_backend/metadata_database_index_on_disk.cc:151:
if (batch)
On 2014/07/16 04:52:24, tzik wrote:
> can we remove this check?
yes. Done.

[peria, 2014-07-16 23:51:55]

The CQ bit was checked by peria@chromium.org

[commit-bot: I haz the power, 2014-07-16 23:53:13]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/peria@chromium.org/393953010/3

[commit-bot: I haz the power, 2014-07-17 08:14:37]

Change committed as 283705