Split recursive Copy/Move into async tasks and support cross operation (in local case)

Split recursive Copy/Move into async tasks and support cross operation (in local case)

Also get cross-filesystem operation working
(as far as both belong to LocalFileSystemOperation).

(I'll make related clean-ups in follow-up patches later)

Similarly to dividing Remove change this basically makes
end-to-end recursive copy/move operation SLOW, while
concurrent tasks won't be blocked for a long time.

With config: 200 files, 120 dirs, 4-level tree, total 100MB

* Copy:
Before this change: Ave:164.01 msec, Stddev:  3.534 msec 
After this change:  Ave:228.34 msec, Stddev: 36.014 msec

* Move (copy+remove after this change):
Before this change: Ave: 87.76 msec, Stddev: 4.631 msec
After this change:  Ave:392.12 msec, Stddev:35.340 msec

Patch from: https://codereview.chromium.org/12018017/
Try results: https://codereview.chromium.org/12051010/

BUG=110121, 146215
TEST=content_browsertests:FileSystemLayoutTest.{OpCopy,OpMove,CrossFilesystemOp}

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=179128

[kinuko, 2013-01-23 06:24:01]

I'll add more tests (in separate patches) but bots look happy
(https://codereview.chromium.org/12051010/) and it works fine in my local manual
test.

Can you take a look? Thanks!

[tzik, 2013-01-24 05:19:24]

lgtm

https://codereview.chromium.org/12036022/diff/4016/webkit/fileapi/cross_opera...
File webkit/fileapi/cross_operation_delegate.cc (right):

https://codereview.chromium.org/12036022/diff/4016/webkit/fileapi/cross_opera...
webkit/fileapi/cross_operation_delegate.cc:128: }
For same_file_system && operation_type == MOVE case, we might perform the
operation efficiently without recursive operation.
Could you leave TODO comment to optimize the case?

[kinuko, 2013-01-25 04:31:43]

Addressed comments and merged memory leak fix.

https://codereview.chromium.org/12036022/diff/4016/webkit/fileapi/cross_opera...
File webkit/fileapi/cross_operation_delegate.cc (right):

https://codereview.chromium.org/12036022/diff/4016/webkit/fileapi/cross_opera...
webkit/fileapi/cross_operation_delegate.cc:128: }
On 2013/01/24 05:19:24, tzik wrote:
> For same_file_system && operation_type == MOVE case, we might perform the
> operation efficiently without recursive operation.
> Could you leave TODO comment to optimize the case?

Done.

[tzik, 2013-01-28 02:21:53]

lgtm