Add FileSystemID parameter to IsolatedContext::RegisterFileSystemForPath.

Add FileSystemID parameter to IsolatedContext::RegisterFileSystemForPath.

With this change, nested filesystems mounted onto isolated context
can remember its original filesystem id, that unblocks the issue 370782
of drag-and-drop support in chromeos::FileSystemBackend.

BUG=370782, 386062
TBR=kaznacheev, benwells, dmichael, sky

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=278666

[tzik, 2014-06-20 03:30:30]

lgtm

[kinaba, 2014-06-20 03:40:02]

On 2014/06/20 03:30:30, tzik wrote:
> lgtm

Added TBR for changes affected by the added parameter (just filled with
a default value and thus there won't be no behavioral change.)
kaznacheev: (*/devtools)
benwells: (*/extensions, extensions/*)
dmichael: (*/pepper)
sky: (content/browser/*)

[kinaba, 2014-06-20 03:40:50]

The CQ bit was checked by kinaba@chromium.org

[commit-bot: I haz the power, 2014-06-20 03:44:55]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/kinaba@chromium.org/341043008/1

[commit-bot: I haz the power, 2014-06-20 09:05:48]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  android_dbg_triggered_tests on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/android_dbg_triggered...)
  win_chromium_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/win_chromium_rel/buil...)

[commit-bot: I haz the power, 2014-06-20 09:31:42]

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

[commit-bot: I haz the power, 2014-06-20 09:31:44]

Try jobs failed on following builders:
  android_dbg_triggered_tests on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/android_dbg_triggered...)

[kinaba, 2014-06-20 09:32:42]

The CQ bit was checked by kinaba@chromium.org

[commit-bot: I haz the power, 2014-06-20 09:34:56]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/kinaba@chromium.org/341043008/1

[commit-bot: I haz the power, 2014-06-20 10:40:19]

Change committed as 278666

[dmichael (off chromium), 2014-06-20 14:54:54]

pepper lgtm