Pepper: Ensure FileIO host cleans up before FileSystem host destructs.

Pepper: FileIO holds FileSystem ref with scoped_refptr<Resource>.

1) Use a scoped_refptr to keep the FileSystemResource alive.
ScopedPPResource isn't safe for this purpose.
2) Make sure that the FileIOResource always sends a close message, so
the FileIO host can unhook from the FileSystemHost before the latter is
destroyed. Due to refcounting, the destruction order is in some cases not
what we want.

R=teravest@chromium.org
BUG=330809, 330859
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=242646

[bbudge, 2013-12-27 19:17:41]

https://codereview.chromium.org/121813002/diff/1/ppapi/proxy/file_io_resource.h
File ppapi/proxy/file_io_resource.h (right):

https://codereview.chromium.org/121813002/diff/1/ppapi/proxy/file_io_resource...
ppapi/proxy/file_io_resource.h:27: class FileSystemResource;
I'll remove this.

[teravest, 2013-12-27 19:19:04]

lgtm

Thanks for doing this. Looks good after removing that unnecessary line.

[bbudge, 2013-12-27 20:04:28]

I decided to roll the Close change into this one. Updated the issue
to reflect that and explain what this fixes.

https://codereview.chromium.org/121813002/diff/100001/content/browser/rendere...
File content/browser/renderer_host/pepper/pepper_file_io_host.cc (right):

https://codereview.chromium.org/121813002/diff/100001/content/browser/rendere...
content/browser/renderer_host/pepper/pepper_file_io_host.cc:410: check_quota_ =
false;
This ensures we don't do this twice.

[teravest, 2013-12-27 20:13:02]

lgtm

Thanks!

[commit-bot: I haz the power, 2013-12-27 20:44:18]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/bbudge@chromium.org/121813002/100001

[bbudge, 2013-12-27 22:53:52]

Committed patchset #2 manually as r242646 (presubmit successful).