[Sync] Made some sync session member functions const

[Sync] Made some sync session member functions const

In particular, split SyncSession::status_controller() into status_controller()
and mutable_status_controller().

Also remove some dead code.

Propagate const methods throughout sync code.

This is in preparation for an upcoming change that makes
ModelChangingSyncerCommand post on only the threads it needs to.

BUG=97832
TEST=


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=111329

[akalin, 2011-11-22 03:17:00]

+zea for review

This CL is easier to review than it looks; the meat of the changes are in the
sessions/* files, and all the changes in engine/* are just mechanical.

[Nicolas Zea, 2011-11-22 20:18:45]

LGTM with nits

http://codereview.chromium.org/8638001/diff/6037/chrome/browser/sync/engine/p...
File chrome/browser/sync/engine/process_updates_command.cc (right):

http://codereview.chromium.org/8638001/diff/6037/chrome/browser/sync/engine/p...
chrome/browser/sync/engine/process_updates_command.cc:46:
syncable::WriteTransaction trans(FROM_HERE, syncable::SYNCER, dir);
Any reason you moved the transaction up? Seems better to open it after
conditional, therefore avoiding locking unnecessarily.

http://codereview.chromium.org/8638001/diff/6037/chrome/browser/sync/sessions...
File chrome/browser/sync/sessions/status_controller.cc (right):

http://codereview.chromium.org/8638001/diff/6037/chrome/browser/sync/sessions...
chrome/browser/sync/sessions/status_controller.cc:44:
&GetOrCreateModelSafeGroupState(
move to prev line

http://codereview.chromium.org/8638001/diff/6037/chrome/browser/sync/sessions...
chrome/browser/sync/sessions/status_controller.cc:56:
&GetOrCreateModelSafeGroupState(
move to prev line

[akalin, 2011-11-22 22:06:07]

Addressed all comments.  Committing after trybots.

http://codereview.chromium.org/8638001/diff/6037/chrome/browser/sync/engine/p...
File chrome/browser/sync/engine/process_updates_command.cc (right):

http://codereview.chromium.org/8638001/diff/6037/chrome/browser/sync/engine/p...
chrome/browser/sync/engine/process_updates_command.cc:46:
syncable::WriteTransaction trans(FROM_HERE, syncable::SYNCER, dir);
On 2011/11/22 20:18:45, nzea wrote:
> Any reason you moved the transaction up? Seems better to open it after
> conditional, therefore avoiding locking unnecessarily.

Definitely unintentional.  Fixed.

http://codereview.chromium.org/8638001/diff/6037/chrome/browser/sync/sessions...
File chrome/browser/sync/sessions/status_controller.cc (right):

http://codereview.chromium.org/8638001/diff/6037/chrome/browser/sync/sessions...
chrome/browser/sync/sessions/status_controller.cc:44:
&GetOrCreateModelSafeGroupState(
On 2011/11/22 20:18:45, nzea wrote:
> move to prev line

Done.

http://codereview.chromium.org/8638001/diff/6037/chrome/browser/sync/sessions...
chrome/browser/sync/sessions/status_controller.cc:56:
&GetOrCreateModelSafeGroupState(
On 2011/11/22 20:18:45, nzea wrote:
> move to prev line

Done.

[commit-bot: I haz the power, 2011-11-23 01:23:16]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/akalin@chromium.org/8638001/9001

[commit-bot: I haz the power, 2011-11-23 01:23:25]

Can't apply patch for file chrome/browser/sync/engine/syncer.cc.
While running patch -p1 --forward --force;
patching file chrome/browser/sync/engine/syncer.cc
Hunk #1 succeeded at 84 (offset 28 lines).
Hunk #2 succeeded at 181 (offset 25 lines).
Hunk #3 succeeded at 219 (offset 23 lines).
Hunk #4 FAILED at 217.
Hunk #5 succeeded at 247 with fuzz 1 (offset 20 lines).
Hunk #6 succeeded at 261 (offset 19 lines).
Hunk #7 succeeded at 275 (offset 19 lines).
Hunk #8 succeeded at 322 (offset 17 lines).
1 out of 8 hunks FAILED -- saving rejects to file
chrome/browser/sync/engine/syncer.cc.rej

[commit-bot: I haz the power, 2011-11-23 01:56:25]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/akalin@chromium.org/8638001/16002

[akalin, 2011-11-23 02:53:05]

I introduced a (latent) bug in StatusController.

I fixed it, and will check in as soon as trybots pass.

None of the tests in this CL, caught it, but the ones in
http://codereview.chromium.org/8637006/ did.

[commit-bot: I haz the power, 2011-11-23 06:50:18]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/akalin@chromium.org/8638001/21003

[commit-bot: I haz the power, 2011-11-23 07:55:21]

Change committed as 111329