Reviewed by Beth Dakin.
CSS @import statements can cause DocLoader to use a dead Frame pointer. https://bugs.webkit.org/show_bug.cgi?id=19618 The fix is to get rid of the Frame pointer on DocLoader. I also took this opportunity to clean up Document::detach a little to make it clear why we clear the m_frame pointer there, and to note that in the future we should stop using Node::detach to mean "tear down the whole rendering tree and detach from the frame". Test: I don't know how to make a good test for this, the test we have is network timing dependent and does not make a good layout test. * dom/Document.cpp: (WebCore::Document::Document): (WebCore::Document::detach): (WebCore::Document::clearFramePointer): * dom/Document.h: * loader/DocLoader.cpp: (WebCore::DocLoader::frame): * loader/DocLoader.h: git-svn-id: http://svn.webkit.org/repository/webkit/trunk@34815 268f45cc-cd09-0410-ab3c-d52691b4dbfc