https://bugs.webkit.org/show_bug.cgi?id=13631

Reviewed by Darin Adler.

- More CachedFrame destruction work.
- Including related Frame and FrameLoader changes and cleanup.

No new tests. (No change in behavior, current tests pass).

* history/CachedFrame.cpp:
(WebCore::CachedFrameBase::restore): Rebuild up the whole FrameTree when restoring.
(WebCore::CachedFrame::CachedFrame): Tear down the entire FrameTree when caching.
(WebCore::CachedFrame::destroy): For child frames that are being destroyed while in
  the PageCache, do lightweight cleanup to:
  A - Prevent referring to a stale Page object.
  B - Prevent World Leaks of WebKit objects.

* loader/FrameLoader.cpp:
(WebCore::FrameLoader::stopAllLoaders): stopAllLoaders() should never be called on Frames that are
  in the PageCache. ASSERT that fact.
(WebCore::FrameLoader::open): Remove a bogus release-build workaround, as the comment right above it
  explains it is not effective, and it'd be better to see the crash locally instead of downstream.
(WebCore::FrameLoader::closeAndRemoveChild): Make sure the owner element has a page pointer before
  referencing it.
(WebCore::FrameLoader::detachFromParent): Use the new detachViewsAndDocumentLoader() call
(WebCore::FrameLoader::detachViewsAndDocumentLoader): Does lightweight cleanup of client (WebKit) objects.
* loader/FrameLoader.h:

* page/Frame.cpp:
(WebCore::Frame::detachFromPage): Simply clear the Page pointer without doing any other work.
(WebCore::Frame::pageDestroyed): Use the new detachFromPage().
* page/Frame.h:

WebKit/mac: More partial work towards "Page Cache should support pages with Frames"
https://bugs.webkit.org/show_bug.cgi?id=13631

Reviewed by Darin Adler.

* WebView/WebHTMLView.mm:
(-[WebHTMLView _topHTMLView]): Rework the ASSERT in this method to reflect the
  reality of calling this method for pages currently in the PageCache.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@47999 268f45cc-cd09-0410-ab3c-d52691b4dbfc