Fix a FORWARD_NULL defect reported by Coverity....

Fix a FORWARD_NULL defect reported by Coverity.

In ChromeClientImpl::focus(), we need to do a null check
for 'delegate' before calling
delegate->FocusAccessibilityObject().

R=klink
BUG=http://crbug.com/17101
TEST=none

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=21296

[wtc, 2009-07-22 02:00:46]

Hi Jonas,

The obvious fix is to change
  if (focused_acc_obj) {
    delegate->FocusAccessibilityObject(focused_acc_obj);
  }
to
  if (focused_acc_obj && delegate) {
    delegate->FocusAccessibilityObject(focused_acc_obj);
  }

But I think that entire piece of code is not necessary
if 'delegate' is NULL, so I moved it all into if (delegate).
I hope this is correct.

[Jonas Klink (Google), 2009-07-22 17:34:45]

LGTM