WebCrypto: Test error delivery during process().

WebCrypto: Test error delivery during process().

BUG=245025
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=154973

[abarth-chromium, 2013-07-25 22:20:50]

LGTM

delete this -> :(

[eroman, 2013-07-25 22:35:09]

Regarding the "delete this":

The alternatives I considered are:


(1) Have blink delete the object upon receiving completion. i.e

   m_result.completeWithError();
   // At this point |this| has been deleted by blink

  Cons:
     - subtle that deletion happens as a sideffect (could rename the result
method to clarify that); need to return immediately to avoid any use after
frees.

     - doesn't allow the embedder's WebCryptoOperation implementation to be
referene-counted, since calling delete directly. It is likely that some of the
blink-side implementations will post a task to a worker thread and hence be
reference counted; this requires creating an extra wrapper for delete to be
called on.

(2) Make WebCryptoOperation reference-counted, by adding virtual methods to its
interface for ref() and deref().

  Cons:
    - forces the implementations to be reference counted
    - has the same subtlety that calling into m_result->* may release the final
reference and end up deleting |this|.


I am not enthusiastic about either of the two options above, since the error
case is a use-after-free rather than a memory leak.

What do you think?

[eroman, 2013-07-25 22:46:31]

I will prepare a possible changelist for more automatic memory management and
see how you like it!

(basically a variation of idea #2)

[abarth-chromium, 2013-07-25 22:49:20]

On 2013/07/25 22:46:31, eroman wrote:
> I will prepare a possible changelist for more automatic memory management and
> see how you like it!

I don't fully understand who owns each of these objects.  Hopefully that will
become clearer in your CL.

[commit-bot: I haz the power, 2013-07-26 01:30:31]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/eroman@chromium.org/20421002/1

[commit-bot: I haz the power, 2013-07-26 03:47:27]

Change committed as 154973