Remove incorrect assertion

Remove incorrect assertion. This used to say
DCHECK(!is_asynchronous_load_suspended || request_info_);
When I made the request info a POD structure that's copied I should have just remove this check since that's really what it was testing.

TEST=manual, no extra DCHECK hit
BUG=none
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=98976

[brettw, 2011-08-30 23:23:40]

I think the PDF tests didn't show this because they're probably only run in
release mode with no debug checks.

[ddorwin, 2011-08-30 23:36:07]

LGTM.

Thanks. Actually, I think this is always false in the PDF case. It's other
plugins that do suspend load that would assert.