Merge 135804 - Check for empty perContextData while creating NP V8 Object.

Merge 135804 - Check for empty perContextData while creating NP V8 Object.
https://bugs.webkit.org/show_bug.cgi?id=98448

Patch by Istiaque Ahmed <lazyboy@chromium.org>; on 2012-11-26
Reviewed by Adam Barth.

Fixes crash in npCreateV8ScriptObject(), if NP Invoke is called from a document
that is no longer displayed in frame (isCurrentlyDisplayedInFrame() ==
false), we have empty perContextData and this results in invalid memory access.

Source/WebCore:

Test: platform/chromium/plugins/empty-per-context-data.html

* bindings/v8/NPV8Object.cpp:
(WebCore::npCreateV8ScriptObject):

LayoutTests:

* platform/chromium/plugins/empty-per-context-data-expected.txt: Added.
* platform/chromium/plugins/empty-per-context-data.html: Added.
* platform/chromium/plugins/resources/script-container.html: Added.

TBR=commit-queue@webkit.org
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=136064