Drive API: Simplify lifetime management of child requests in BatchUploadRequest.

Drive API: Simplify lifetime management of child requests in BatchUploadRequest.

Previously BatchableRequestBase can be used both as a normal request and as a
child request in BatchUploadRequest. Even when BatchableRequestBase is used as
child request, its lifetime must be managed by RequestSender, and it makes hard
to track the lifetime in BatchUploadRequest.

To simplify lifetime management in BatchUploadRequest, the CL extracts the core
part of BatchableRequestBase into BatchableDelegate, and lets BatchUploadRequest
use the delegate as a child request. Because the delegate is nolonger owned by
RequestSender, BatchUploadRequest can own its child requests without caring
RequestSender.

BUG=451917
TEST=googleapis_unittests

Committed: https://crrev.com/3cea41ac2c0288917be7c07039ac081e9dface49
Cr-Commit-Position: refs/heads/master@{#329809}

[hirono, 2015-05-12 08:46:52]

hirono@chromium.org changed reviewers:
+ kinaba@chromium.org

[hirono, 2015-05-12 08:46:52]

PTAL, thanks!

[kinaba, 2015-05-14 04:16:40]

lgtm

https://codereview.chromium.org/1132693006/diff/60001/google_apis/drive/drive...
File google_apis/drive/drive_api_requests.cc (right):

https://codereview.chromium.org/1132693006/diff/60001/google_apis/drive/drive...
google_apis/drive/drive_api_requests.cc:1409: // Pass onwership of |delegate| so
that it is deleted after notifying.
I think there's a room for improvement on this comment. At the first time I read
"so that it is deleted after notifying" as saying "so that it is *deleted*", but
only after careful inspection of the CL I realized that your intention is rather
"so that it is *after*".

How about:

// Pass onwership of |delegate| so that child_requests_.clear() won't
// kill the delegate. It has to be deleted after the notification.

[hirono, 2015-05-14 04:43:13]

Thank you!

https://codereview.chromium.org/1132693006/diff/60001/google_apis/drive/drive...
File google_apis/drive/drive_api_requests.cc (right):

https://codereview.chromium.org/1132693006/diff/60001/google_apis/drive/drive...
google_apis/drive/drive_api_requests.cc:1409: // Pass onwership of |delegate| so
that it is deleted after notifying.
On 2015/05/14 04:16:40, kinaba wrote:
> I think there's a room for improvement on this comment. At the first time I
read
> "so that it is deleted after notifying" as saying "so that it is *deleted*",
but
> only after careful inspection of the CL I realized that your intention is
rather
> "so that it is *after*".
> 
> How about:
> 
> // Pass onwership of |delegate| so that child_requests_.clear() won't
> // kill the delegate. It has to be deleted after the notification.

Thank you for the suggestion. I just copied the comment.

[hirono, 2015-05-14 04:43:18]

The CQ bit was checked by hirono@chromium.org

[hirono, 2015-05-14 04:43:19]

The patchset sent to the CQ was uploaded after l-g-t-m from kinaba@chromium.org
Link to the patchset: https://codereview.chromium.org/1132693006/#ps80001
(title: "Improve comment.")

[commit-bot: I haz the power, 2015-05-14 04:43:29]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1132693006/80001

[commit-bot: I haz the power, 2015-05-14 05:38:49]

Committed patchset #5 (id:80001)

[commit-bot: I haz the power, 2015-05-14 05:40:26]

Patchset 5 (id:??) landed as
https://crrev.com/3cea41ac2c0288917be7c07039ac081e9dface49
Cr-Commit-Position: refs/heads/master@{#329809}