Print cross-domain access errors on calling window rather than target.

Print cross-domain access errors on calling window rather than target.

Currently, on cross-domain access errors, such as when a frame is
denied permission to navigate another frame,
LocalDOMWindow::printErrorMessage is called on the target window,
rather than the calling window.  This CL changes these errors to be
printed on the calling window instead.  There doesn't appear to be a
good reason for printing on the target, and it seems that IE and
Firefox already print similar messages on the source -- see
https://codereview.chromium.org/1085973003/ for more discussion.
Printing on the calling window makes more sense, and it makes it
easier to refactor error messages to work with out-of-process iframes 
(which will happen in https://codereview.chromium.org/1085973003/).

BUG=478254
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=194200

[alexmos, 2015-04-20 23:26:03]

alexmos@chromium.org changed reviewers:
+ dcheng@chromium.org, haraken@chromium.org

[alexmos, 2015-04-20 23:40:16]

Please take a look.

[haraken, 2015-04-21 04:44:34]

The change looks good.

Can we add a test for this?

[alexmos, 2015-04-21 22:36:35]

On 2015/04/21 04:44:34, haraken wrote:
> The change looks good.
> 
> Can we add a test for this?

Test added.  In layout tests, it didn't seem possible to tell which window a
console error was printed to in the output, so I added a WebFrameTest to check
that these errors go to the calling window.  I'll also have a Chromium-side test
for this at https://codereview.chromium.org/1098763003/.

[haraken, 2015-04-22 05:14:07]

LGTM

[alexmos, 2015-04-22 05:57:52]

The CQ bit was checked by alexmos@chromium.org

[commit-bot: I haz the power, 2015-04-22 05:58:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1096173003/20001

[commit-bot: I haz the power, 2015-04-22 07:24:44]

Committed patchset #2 (id:20001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=194200