Dispatch FileSystemOperationRunner callbacks always synchronously

Dispatch FileSystemOperationRunner callbacks always synchronously

- Re-post callbacks only if they are called synchronously
- Always return a valid operation ID (even if it's finished immediately)
- Fix cancel callbacks ordering

BUG=279288
TEST=existing tests
TBR=hidehiko@chromium.org, tzik@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=221384

[kinuko, 2013-09-03 22:10:39]

Abe-san, this one just come up to me as an alternative patch in the same
direction as https://codereview.chromium.org/23477026/.  I think this change
works ok with correct callback ordering.  Can you take a look to see if this
could help?

[hidehiko, 2013-09-04 03:22:55]

On 2013/09/03 22:10:39, kinuko wrote:
> Abe-san, this one just come up to me as an alternative patch in the same
> direction as https://codereview.chromium.org/23477026/.  I think this change
> works ok with correct callback ordering.  Can you take a look to see if this
> could help?

lgtm. Thank you for working on this!

[kinuko, 2013-09-04 15:28:55]

tzik: can you also do a cross-review?  Thanks,

[tzik, 2013-09-05 03:35:20]

lgtm

https://codereview.chromium.org/23898002/diff/27001/webkit/browser/fileapi/fi...
File webkit/browser/fileapi/file_system_operation_runner.h (right):

https://codereview.chromium.org/23898002/diff/27001/webkit/browser/fileapi/fi...
webkit/browser/fileapi/file_system_operation_runner.h:236: void
DidFinish(OperationHandle handle,
Can we replace these OperationHandle with const ref?

[kinuko, 2013-09-05 05:51:02]

Added tests, and slightly modified the existing cancel behavior so that we
consistently return INVALID_OPERATION error if it has failed to stop the
inflight operation. (Confirmed that it doesn't break existing JS behavior)

https://codereview.chromium.org/23898002/diff/27001/webkit/browser/fileapi/fi...
File webkit/browser/fileapi/file_system_operation_runner.h (right):

https://codereview.chromium.org/23898002/diff/27001/webkit/browser/fileapi/fi...
webkit/browser/fileapi/file_system_operation_runner.h:236: void
DidFinish(OperationHandle handle,
On 2013/09/05 03:35:20, tzik wrote:
> Can we replace these OperationHandle with const ref?

Done.

[kinuko, 2013-09-05 07:31:52]

On 2013/09/05 05:51:02, kinuko wrote:
> Added tests, and slightly modified the existing cancel behavior so that we
> consistently return INVALID_OPERATION error if it has failed to stop the
> inflight operation. (Confirmed that it doesn't break existing JS behavior)

Well, I dropped this part but just added tests.  I'll send a separate review for
the part that modifies the existing behavior.
Will be submitting...

[kinuko, 2013-09-05 11:23:27]

TBR-ing avi for one-line content_tests.gypi change.

[kinuko, 2013-09-05 11:24:44]

Committed patchset #4 manually as r221384 (presubmit successful).