Reviewed by Darin Adler

        <rdar://problem/3541409> - Further FrameLoader and page cache cleanup

        * history/CachedFrame.cpp:
        (WebCore::CachedFrame::restore): Moved updatePlatformScriptObjects() here.

        * loader/FrameLoader.cpp:
        (WebCore::FrameLoader::commitProvisionalLoad): Rolled opened() into this method.  This method was
          the only caller and - in the future - will benefit from doing parts of opened()'s work differently.
        (WebCore::FrameLoader::open): Split off per-frame logic into open(CachedFrame&) method.
        (WebCore::FrameLoader::closeAndRemoveChild): Added.  Do the non-tree related cleanup that
          FrameTree::removeChild() used to do.
        (WebCore::FrameLoader::detachFromParent): Call ::closeAndRemoveChild() instead.
        (WebCore::FrameLoader::cachePageForHistoryItem): Perform the "can cache page" check here.
        * loader/FrameLoader.h:

        * page/FrameTree.cpp:
        (WebCore::FrameTree::removeChild): Just remove the Frame from the tree.  Closing it and other
          cleanup is the responsibility of the FrameLoader.
        * page/FrameTree.h:
        (WebCore::FrameTree::detachFromParent): Added to just clear a Frame's parent pointer



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@40870 268f45cc-cd09-0410-ab3c-d52691b4dbfc