Cherry-pick "Export WebCore::forgetV8ObjectForNPObject"

Bug: 14582835

Original CL description:

    Export WebCore::forgetV8ObjectForNPObject

    This is required for de-associating an NPObject from an existing V8 wrapper,
    so we don't pull any of the wrapper's custom properties into the context of
    a new page when navigating to it.


    Review URL:

    git-svn-id: svn:// bbb929c8-8fbe-4397-9dbb-9b2b20218538

Change-Id: I7e3587dc166391679f17b233f98748bd6e9000a7
2 files changed