[WebSocket] Remove unnecessary harmful check on the Page instance associated with the Document

[WebSocket] Remove unnecessary harmful check on the Page instance associated with the Document

Blink r148941
(https://src.chromium.org/viewvc/blink?revision=148941&view=revision)
separeted createUniqueIdentifier() from ProgressTracker. So, we no
longer need to check if the Page is null or not.

Blink r160310
(https://src.chromium.org/viewvc/blink?revision=160310&view=revision)
added NewWebSocketChannelImpl::document() and it expects m_identifier
to be non-null. But it isn't when the Page was null on construction.
This leads to crash on document() call.

Let's just remove the Page null-ness check.

BUG=none

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=187366

[tyoshino (SeeGerritForStatus), 2014-12-17 09:19:48]

tyoshino@chromium.org changed reviewers:
+ yhirano@chromium.org

[tyoshino (SeeGerritForStatus), 2014-12-17 09:24:08]

On 2014/12/17 09:19:52, tyoshino wrote:

This is needed to land https://codereview.chromium.org/785933005/

[Mike West, 2014-12-17 09:36:26]

mkwst@chromium.org changed reviewers:
+ mkwst@chromium.org

[Mike West, 2014-12-17 09:36:26]

LGTM.

[yhirano, 2014-12-17 10:03:21]

lgtm
NewWebSocketChannel => NewWebSocketChannelImpl

[tyoshino (SeeGerritForStatus), 2014-12-17 10:23:27]

On 2014/12/17 10:03:21, yhirano wrote:
> lgtm
> NewWebSocketChannel => NewWebSocketChannelImpl

Done

[tyoshino (SeeGerritForStatus), 2014-12-17 10:23:55]

The CQ bit was checked by tyoshino@chromium.org

[commit-bot: I haz the power, 2014-12-17 10:24:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/806423002/1

[commit-bot: I haz the power, 2014-12-17 11:33:46]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=187366