https://bugs.webkit.org/show_bug.cgi?id=93497

Reviewed by Eric Seidel.

Source/WebCore:

The framework for Chromium "platform" apps executes a big blob of
script during the didCreateScriptContext callback. This blob of scripts
interacts with a bunch of JavaScript objects and triggers a number of
security checks.

When reloading a frame, the didCreateScriptContext is called during
Frame::setDocument (as a consequence of calling
ScriptController::updateDocument). At that time, the SecurityOrigin
object hasn't yet been copied over to the DOMWindow, and we crash
trying to grab it.

The long-term fix for this bug is to fix
https://bugs.webkit.org/show_bug.cgi?id=75793, at which point there
will no longer be a SecurityOrigin object on DOMWindow. In the
meantime, however, we can fix this crash by null checking the
DOMWindow's SecurityOrigin object.

* bindings/generic/BindingSecurity.cpp:
(WebCore::canAccessDocument):

Source/WebKit/chromium:

Test that we don't crash when executing script during the
didCreateScriptContext callback.

* tests/WebFrameTest.cpp:
* tests/data/hello_world.html: Added.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@125077 268f45cc-cd09-0410-ab3c-d52691b4dbfc