[SyncFS] Refine callback helpers

[SyncFS] Refine callback helpers

 * Clean up the implementation
 * Accept FROM_HERE to improve tracability
 * Add another version that takes TaskRunner to relay.

BUG=347425
TEST=unit_tests --gtest_filter=DriveBackendCallbackHelperTest.*
R=peria@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=266127

[tzik, 2014-04-24 04:50:24]

PTL.

I'd like to add a variant use the helper from worker.

[peria, 2014-04-24 05:13:52]

https://codereview.chromium.org/259503004/diff/30001/chrome/browser/sync_file...
File chrome/browser/sync_file_system/drive_backend/callback_helper.h (right):

https://codereview.chromium.org/259503004/diff/30001/chrome/browser/sync_file...
chrome/browser/sync_file_system/drive_backend/callback_helper.h:78:
base::Callback<T> RelayCallbackToTaskRunner(
Please add a test for this template.
Or move this template into "internal" namespace.

https://codereview.chromium.org/259503004/diff/30001/chrome/browser/sync_file...
File chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc
(right):

https://codereview.chromium.org/259503004/diff/30001/chrome/browser/sync_file...
chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc:30:
TEST(DriveBackendCallbackHelperTest, RelayCallbackToCurrentThreadTest) {
Please add a test case for void(void) function.

[tzik, 2014-04-24 07:02:17]

https://codereview.chromium.org/259503004/diff/30001/chrome/browser/sync_file...
File chrome/browser/sync_file_system/drive_backend/callback_helper.h (right):

https://codereview.chromium.org/259503004/diff/30001/chrome/browser/sync_file...
chrome/browser/sync_file_system/drive_backend/callback_helper.h:78:
base::Callback<T> RelayCallbackToTaskRunner(
On 2014/04/24 05:13:53, peria wrote:
> Please add a test for this template.
> Or move this template into "internal" namespace.

Done.

https://codereview.chromium.org/259503004/diff/30001/chrome/browser/sync_file...
File chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc
(right):

https://codereview.chromium.org/259503004/diff/30001/chrome/browser/sync_file...
chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc:30:
TEST(DriveBackendCallbackHelperTest, RelayCallbackToCurrentThreadTest) {
On 2014/04/24 05:13:53, peria wrote:
> Please add a test case for void(void) function.

Done.

[peria, 2014-04-24 07:30:04]

https://codereview.chromium.org/259503004/diff/50001/chrome/browser/sync_file...
File chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc
(right):

https://codereview.chromium.org/259503004/diff/50001/chrome/browser/sync_file...
chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc:34:
RelayCallbackToTaskRunner(
callback_helper.h has 2 interface templates, RelayCallbackToTaskRunner() and
RelayCallbackToCurrentThread().
In addition, we can pass 3 types of functions to them, void(), void(T), and
void(T1, T2).

Please make a test set that can detect which template is wrong.
If #40 fails, we cannot detect whether RelayToTaskRunner<void()> has a bug or
RelayCallbackToTaskRunner() has a bug.

https://codereview.chromium.org/259503004/diff/50001/chrome/browser/sync_file...
chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc:34:
RelayCallbackToTaskRunner(
For example, following combination may detect it.
- RelayCallbackToTaskRunner(void()) : (1)
- RelayCallbackToTaskRunner(void(T))
- RelayCallbackToTaskRunner(void(T,U))
- RelayCallbackToCurrentThread(void()) : comparable with (1)

[tzik, 2014-04-24 07:58:34]

https://codereview.chromium.org/259503004/diff/50001/chrome/browser/sync_file...
File chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc
(right):

https://codereview.chromium.org/259503004/diff/50001/chrome/browser/sync_file...
chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc:34:
RelayCallbackToTaskRunner(
On 2014/04/24 07:30:05, peria wrote:
> callback_helper.h has 2 interface templates, RelayCallbackToTaskRunner() and
> RelayCallbackToCurrentThread().
> In addition, we can pass 3 types of functions to them, void(), void(T), and
> void(T1, T2).
> 
> Please make a test set that can detect which template is wrong.
> If #40 fails, we cannot detect whether RelayToTaskRunner<void()> has a bug or
> RelayCallbackToTaskRunner() has a bug.

I think testing all possible specialization for each simple class is over
pessimistic.

Anyway I change add a .h.pump to generate each pattern of specialization.
I think it's even less error prone now.

[peria, 2014-04-24 08:15:34]

https://codereview.chromium.org/259503004/diff/70001/chrome/browser/sync_file...
File chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc
(right):

https://codereview.chromium.org/259503004/diff/70001/chrome/browser/sync_file...
chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc:34:
RelayCallbackToTaskRunner(
as we chatted f2f, remove this test #34-42 and put a TODO comment to test
RelayCallbackToTaskRunner using another thread.

[tzik, 2014-04-24 09:31:58]

https://codereview.chromium.org/259503004/diff/70001/chrome/browser/sync_file...
File chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc
(right):

https://codereview.chromium.org/259503004/diff/70001/chrome/browser/sync_file...
chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc:34:
RelayCallbackToTaskRunner(
On 2014/04/24 08:15:35, peria wrote:
> as we chatted f2f, remove this test #34-42 and put a TODO comment to test
> RelayCallbackToTaskRunner using another thread.

Done.

[peria, 2014-04-24 09:33:48]

lgtm

[tzik, 2014-04-24 10:19:08]

The CQ bit was checked by tzik@chromium.org

[commit-bot: I haz the power, 2014-04-24 11:07:58]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/tzik@chromium.org/259503004/90001

[commit-bot: I haz the power, 2014-04-24 12:12:12]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-04-24 12:12:12]

Try jobs failed on following builders:
  tryserver.chromium on chromium_presubmit

[tzik, 2014-04-25 02:45:12]

The CQ bit was checked by tzik@chromium.org

[commit-bot: I haz the power, 2014-04-25 02:45:30]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/tzik@chromium.org/259503004/90001

[commit-bot: I haz the power, 2014-04-25 03:38:41]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-04-25 03:38:42]

Try jobs failed on following builders:
  tryserver.chromium on chromium_presubmit

[tzik, 2014-04-25 04:14:16]

Committed patchset #7 manually as r266127 (presubmit successful).