Use the virtual path to set the blob's mime type for CreateSnapshotFile

Use the virtual path to set the blob's mime type for CreateSnapshotFile, otherwise each FS implementation needs to name a temporary file with the same extension.

platform_path might be just a cryptic temporary/cache file name.

BUG=none
TEST=existing tests


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=149316

[kinuko, 2012-07-31 20:04:46]

Can you take a look?

[tzik, 2012-07-31 20:15:05]

LGTM.

[commit-bot: I haz the power, 2012-07-31 22:03:19]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/kinuko@chromium.org/10821096/5

[commit-bot: I haz the power, 2012-07-31 23:32:05]

Change committed as 149316

[michaeln, 2012-08-01 00:12:46]

ooops... apparently i forgot to publish this comment, just curious about the
extra closure indirection.

https://chromiumcodereview.appspot.com/10821096/diff/5/content/browser/fileap...
File content/browser/fileapi/fileapi_message_filter.cc (right):

https://chromiumcodereview.appspot.com/10821096/diff/5/content/browser/fileap...
content/browser/fileapi/fileapi_message_filter.cc:682: FilePath::StringType
extension = virtual_path.Extension();
Based on the CL description, changing from 'platform_path' to 'virtual_path' as
the input to GetWellKnownMimeType makes sense. Is there a reason to add the
layer of indirection with the register_file_callback? Do you anticipate other
callers passing in different closures bound to different methods?

[kinuko, 2012-08-01 00:16:56]

On 2012/08/01 00:12:46, michaeln wrote:
> ooops... apparently i forgot to publish this comment, just curious about the
> extra closure indirection.
> 
>
https://chromiumcodereview.appspot.com/10821096/diff/5/content/browser/fileap...
> File content/browser/fileapi/fileapi_message_filter.cc (right):
> 
>
https://chromiumcodereview.appspot.com/10821096/diff/5/content/browser/fileap...
> content/browser/fileapi/fileapi_message_filter.cc:682: FilePath::StringType
> extension = virtual_path.Extension();
> Based on the CL description, changing from 'platform_path' to 'virtual_path'
as
> the input to GetWellKnownMimeType makes sense. Is there a reason to add the
> layer of indirection with the register_file_callback? Do you anticipate other
> callers passing in different closures bound to different methods?

Maybe I should have added some comments, since Taiju asked the same q.  I just
maxed out the # of args for base::Bind templates.  I could change the max value
but for this small fix instead I added a small indirection.