Allow LoadNavigationErrorPage to run scripts

Allow LoadNavigationErrorPage to run scripts

Move the LoadNavigationErrorPage call from DidFinishDocumentLoad to
RunScriptsAtDocumentReady, because the former is in a
ScriptForbiddenScope and caused an assertion to be triggered in
blink::beforeCallEnteredCallback when the beforeunload listeners were
ran as a part of the navigation.

BUG=590634
Review URL: https://codereview.chromium.org/1837483002

Cr-Commit-Position: refs/heads/master@{#383355}
(cherry picked from commit 2718dfcda8f7afd32b5229d91c3314bf61faf16c)

Committed: https://chromium.googlesource.com/chromium/src/+/74769ef66878333073c4a50624ecf1edd7e07750

[robwu, 2016-03-26 23:40:29]

Description was changed from

==========
Allow LoadNavigationErrorPage to run scripts

Move the LoadNavigationErrorPage call from DidFinishDocumentLoad to
RunScriptsAtDocumentReady, because the former is in a
ScriptForbiddenScope and caused an assertion to be triggered in
blink::beforeCallEnteredCallback when the beforeunload listeners were
ran as a part of the navigation.

BUG=590634

Review URL: https://codereview.chromium.org/1837483002

Cr-Commit-Position: refs/heads/master@{#383355}
(cherry picked from commit 2718dfcda8f7afd32b5229d91c3314bf61faf16c)
==========

to

==========
Allow LoadNavigationErrorPage to run scripts

Move the LoadNavigationErrorPage call from DidFinishDocumentLoad to
RunScriptsAtDocumentReady, because the former is in a
ScriptForbiddenScope and caused an assertion to be triggered in
blink::beforeCallEnteredCallback when the beforeunload listeners were
ran as a part of the navigation.

BUG=590634

Review URL: https://codereview.chromium.org/1837483002

Cr-Commit-Position: refs/heads/master@{#383355}
(cherry picked from commit 2718dfcda8f7afd32b5229d91c3314bf61faf16c)

Committed:
https://chromium.googlesource.com/chromium/src/+/74769ef66878333073c4a50624ec...
==========

[robwu, 2016-03-26 23:40:32]

Committed patchset #1 (id:1) manually as
74769ef66878333073c4a50624ecf1edd7e07750.