[fsp] Simplify ID of provided file systems.

[fsp] Simplify ID of provided file systems.

Previously, the ID was very lenghty, being same as the mount point name. Also,
it contained the extension id, which was too much.

To makes things simple, the ID has been changed to an int only, which is
consistent with setTimeout/setInterval as well as upcoming request's id,
which are just positive numbers.

TEST=unit_tests, browser_tests
BUG=248427
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=259842

[mtomasz, 2014-03-24 06:40:18]

This CL depends on 192573002.

@satorux: PTAL.
@benwells: PTAL at IDL.

Thanks.

[benwells, 2014-03-24 21:31:47]

lgtm

[satorux1, 2014-03-26 07:58:45]

lgtm

https://codereview.chromium.org/209663006/diff/1/chrome/browser/chromeos/exte...
File
chrome/browser/chromeos/extensions/file_system_provider/file_system_provider_api.cc
(right):

https://codereview.chromium.org/209663006/diff/1/chrome/browser/chromeos/exte...
chrome/browser/chromeos/extensions/file_system_provider/file_system_provider_api.cc:57:
// If the |file_system_id| is empty, then it means that registering the file
zero

[mtomasz, 2014-03-26 09:30:15]

https://codereview.chromium.org/209663006/diff/1/chrome/browser/chromeos/exte...
File
chrome/browser/chromeos/extensions/file_system_provider/file_system_provider_api.cc
(right):

https://codereview.chromium.org/209663006/diff/1/chrome/browser/chromeos/exte...
chrome/browser/chromeos/extensions/file_system_provider/file_system_provider_api.cc:57:
// If the |file_system_id| is empty, then it means that registering the file
On 2014/03/26 07:58:45, satorux1 wrote:
> zero

Done.

[mtomasz, 2014-03-27 08:04:33]

The CQ bit was checked by mtomasz@chromium.org

[commit-bot: I haz the power, 2014-03-27 08:05:20]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mtomasz@chromium.org/209663006/70001

[commit-bot: I haz the power, 2014-03-27 12:04:13]

Change committed as 259842