Reviewed extensively and repeatedly by Darin

        <rdar://problem/4887137> - WebCore Back/Forward Cache

        * WebCore.exp:
        * WebCore.xcodeproj/project.pbxproj:

        * bridge/mac/WebCorePageState.h: Removed.
        * bridge/mac/WebCorePageState.mm: Removed.

        * history/BackForwardList.cpp: Added - This largely emulates the design of WebBackForwardList
        (WebCore::BackForwardList::BackForwardList):
        (WebCore::BackForwardList::~BackForwardList):
        (WebCore::BackForwardList::addItem):
        (WebCore::BackForwardList::goBack):
        (WebCore::BackForwardList::goForward):
        (WebCore::BackForwardList::goToItem):
        (WebCore::BackForwardList::backItem):
        (WebCore::BackForwardList::currentItem):
        (WebCore::BackForwardList::forwardItem):
        (WebCore::BackForwardList::backListWithLimit):
        (WebCore::BackForwardList::forwardListWithLimit):
        (WebCore::BackForwardList::capacity):
        (WebCore::BackForwardList::setCapacity):
        (WebCore::BackForwardList::setPageCacheSize):
        (WebCore::BackForwardList::pageCacheSize):
        (WebCore::BackForwardList::clearPageCache):
        (WebCore::BackForwardList::usesPageCache):
        (WebCore::BackForwardList::backListCount):
        (WebCore::BackForwardList::forwardListCount):
        (WebCore::BackForwardList::itemAtIndex):
        (WebCore::BackForwardList::entries):
        (WebCore::BackForwardList::close):
        (WebCore::BackForwardList::closed):
        (WebCore::BackForwardList::removeItem):
        (WebCore::BackForwardList::containsItem):
        (WebCore::BackForwardList::setDefaultPageCacheSize):
        (WebCore::BackForwardList::defaultPageCacheSize):
        * history/BackForwardList.h: Added.

        * history/HistoryItem.cpp: Added - This largely emulates the design of WebBackForwardList
        (WebCore::defaultNotifyHistoryItemChanged):
        (WebCore::HistoryItem::HistoryItem):
        (WebCore::HistoryItem::~HistoryItem):
        (WebCore::HistoryItem::copy):
        (WebCore::HistoryItem::setHasPageCache):
        (WebCore::HistoryItem::retainIconInDatabase):
        (WebCore::HistoryItem::urlString):
        (WebCore::HistoryItem::originalURLString):
        (WebCore::HistoryItem::title):
        (WebCore::HistoryItem::alternateTitle):
        (WebCore::HistoryItem::icon):
        (WebCore::HistoryItem::lastVisitedTime):
        (WebCore::HistoryItem::url):
        (WebCore::HistoryItem::originalURL):
        (WebCore::HistoryItem::target):
        (WebCore::HistoryItem::parent):
        (WebCore::HistoryItem::setAlternateTitle):
        (WebCore::HistoryItem::setURLString):
        (WebCore::HistoryItem::setURL):
        (WebCore::HistoryItem::setOriginalURLString):
        (WebCore::HistoryItem::setTitle):
        (WebCore::HistoryItem::setTarget):
        (WebCore::HistoryItem::setParent):
        (WebCore::HistoryItem::setLastVisitedTime):
        (WebCore::HistoryItem::visitCount):
        (WebCore::HistoryItem::setVisitCount):
        (WebCore::HistoryItem::scrollPoint):
        (WebCore::HistoryItem::setScrollPoint):
        (WebCore::HistoryItem::clearScrollPoint):
        (WebCore::HistoryItem::setDocumentState):
        (WebCore::HistoryItem::documentState):
        (WebCore::HistoryItem::clearDocumentState):
        (WebCore::HistoryItem::isTargetItem):
        (WebCore::HistoryItem::setIsTargetItem):
        (WebCore::HistoryItem::alwaysAttemptToUsePageCache):
        (WebCore::HistoryItem::setAlwaysAttemptToUsePageCache):
        (WebCore::HistoryItem::addChildItem):
        (WebCore::HistoryItem::childItemWithName):
        (WebCore::HistoryItem::recurseToFindTargetItem):
        (WebCore::HistoryItem::targetItem):
        (WebCore::HistoryItem::pageCache):
        (WebCore::HistoryItem::children):
        (WebCore::HistoryItem::hasChildren):
        (WebCore::HistoryItem::formContentType):
        (WebCore::HistoryItem::formReferrer):
        (WebCore::HistoryItem::rssFeedReferrer):
        (WebCore::HistoryItem::setRSSFeedReferrer):
        (WebCore::HistoryItem::setFormInfoFromRequest):
        (WebCore::HistoryItem::formData):
        (WebCore::HistoryItem::mergeAutoCompleteHints):
        (WebCore::HistoryItem::hasPageCache):
        (WebCore::timer): Function to manage the global release timer
        (WebCore::pendingPageCacheToRelease): Function to manage the global queue of caches to be released
        (WebCore::HistoryItem::releasePageCache):
        (WebCore::closeObjectsInPendingPageCaches):
        (WebCore::HistoryItem::releaseAllPendingPageCaches):
        (WebCore::HistoryItem::scheduleRelease):
        (WebCore::HistoryItem::print):
        * history/HistoryItem.h: Added.
        * history/mac/HistoryItemMac.mm: Added.
        (WebCore::HistoryItem::viewState): In the future we need a platform agnostic way to manage the view state
        (WebCore::HistoryItem::setViewState):
        (WebCore::HistoryItem::getTransientProperty): Transient properties are, for now, only a Mac concept
        (WebCore::HistoryItem::setTransientProperty):

        * history/HistoryItemTimer.cpp: Added
        (WebCore::HistoryItemTimer::HistoryItemTimer): We need a specific class to be the history item timer because
        WebCore::Timers only work when you have an instance of an object, but the caches pending release is a static concept
        (WebCore::HistoryItemTimer::isActive):
        (WebCore::HistoryItemTimer::schedule):
        (WebCore::HistoryItemTimer::invalidate):
        (WebCore::HistoryItemTimer::callReleasePageCache):
        * history/HistoryItemTimer.h: Added.

        * history/PageCache.cpp Added - This is a class that contains the fields that used to be in an NSDictionary in WebKit
        (WebCore::PageCache::PageCache):
        (WebCore::PageCache::setPageState):
        (WebCore::PageCache::~PageCache):
        (WebCore::PageCache::pageState):
        (WebCore::PageCache::setDocumentLoader):
        (WebCore::PageCache::documentLoader):
        (WebCore::PageCache::setTimeStamp):
        (WebCore::PageCache::setTimeStampToNow):
        (WebCore::PageCache::timeStamp):
        * history/PageCache.h: Added.
        * history/mac/PageCacheMac.mm: Added.
        (WebCore::PageCache::close):
        (WebCore::PageCache::setDocumentView): In the future we need a platform agnostic way to manage the documentView
        (WebCore::PageCache::documentView):

        * loader/DocumentLoader.cpp:
        (WebCore::DocumentLoader::loadFromPageCache):
        (WebCore::DocumentLoader::setLoadingFromPageCache): 
        (WebCore::DocumentLoader::isLoadingFromPageCache):
        (WebCore::DocumentLoader::originalURL):
        (WebCore::DocumentLoader::requestURL):
        (WebCore::DocumentLoader::responseURL):
        (WebCore::DocumentLoader::responseMIMEType):
        * loader/DocumentLoader.h:

        * loader/FrameLoader.cpp: Responsibilities previously scattered in WebKit but concentrated in WebView and WebFrame 
          are now here, where they should be.
        (WebCore::FrameLoader::clear):
        (WebCore::FrameLoader::restoreDocumentState):
        (WebCore::FrameLoader::goBackOrForward):
        (WebCore::FrameLoader::provisionalLoadStarted):
        (WebCore::FrameLoader::canCachePage):
        (WebCore::FrameLoader::commitProvisionalLoad):
        (WebCore::FrameLoader::transitionToCommitted):
        (WebCore::FrameLoader::open):
        (WebCore::FrameLoader::didFirstLayout):
        (WebCore::FrameLoader::dispatchDidChangeLocationWithinPage):
        (WebCore::FrameLoader::dispatchDidFinishLoadToClient):
        (WebCore::FrameLoader::updateGlobalHistoryForStandardLoad): Marked for usage in future GlobalHistory (uses client for now)
        (WebCore::FrameLoader::updateGlobalHistoryForReload): Ditto
        (WebCore::FrameLoader::shouldGoToHistoryItem):
        (WebCore::FrameLoader::addExtraFieldsToRequest):
        (WebCore::FrameLoader::addHistoryItemForFragmentScroll):
        (WebCore::FrameLoader::loadProvisionalItemFromPageCache):
        (WebCore::FrameLoader::createPageCache):
        (WebCore::FrameLoader::shouldTreatURLAsSameAsCurrent):
        (WebCore::FrameLoader::createItem):
        (WebCore::FrameLoader::addBackForwardItemClippedAtTarget):
        (WebCore::FrameLoader::createItemTree):
        (WebCore::FrameLoader::saveScrollPositionAndViewStateToItem):
        (WebCore::FrameLoader::restoreScrollPositionAndViewState):
        (WebCore::FrameLoader::purgePageCache):
        (WebCore::FrameLoader::invalidateCurrentItemPageCache):
        (WebCore::FrameLoader::saveDocumentState):
        (WebCore::FrameLoader::loadItem):
        (WebCore::FrameLoader::urlsMatchItem):
        (WebCore::FrameLoader::goToItem):
        (WebCore::FrameLoader::recursiveGoToItem):
        (WebCore::FrameLoader::childFramesMatchItem):
        (WebCore::FrameLoader::updateHistoryForStandardLoad):
        (WebCore::FrameLoader::updateHistoryForClientRedirect):
        (WebCore::FrameLoader::updateHistoryForBackForwardNavigation):
        (WebCore::FrameLoader::updateHistoryForReload):
        (WebCore::FrameLoader::updateHistoryForInternalLoad):
        (WebCore::FrameLoader::updateHistoryForCommit):
        (WebCore::FrameLoader::saveDocumentAndScrollState):
        (WebCore::FrameLoader::currentHistoryItem):
        (WebCore::FrameLoader::previousHistoryItem):
        (WebCore::FrameLoader::provisionalHistoryItem):
        (WebCore::FrameLoader::setCurrentHistoryItem):
        (WebCore::FrameLoader::setPreviousHistoryItem):
        (WebCore::FrameLoader::setProvisionalHistoryItem):
        * loader/FrameLoader.h:

        * loader/FrameLoaderClient.h:

        * loader/mac/DocumentLoaderMac.mm:
        (WebCore::DocumentLoader::DocumentLoader):
        (WebCore::DocumentLoader::getResponseRefreshAndModifiedHeaders):
        (WebCore::DocumentLoader::commitIfReady):
        (WebCore::DocumentLoader::urlForHistory):

        * loader/mac/FrameLoaderMac.mm:
        (WebCore::FrameLoader::load):
        (WebCore::FrameLoader::startLoading):
        (WebCore::FrameLoader::receivedMainResourceError):
        (WebCore::FrameLoader::continueFragmentScrollAfterNavigationPolicy):
        (WebCore::FrameLoader::opened):
        (WebCore::FrameLoader::dataURLBaseFromRequest):
        (WebCore::FrameLoader::didChangeTitle):
        (WebCore::FrameLoader::continueLoadAfterNavigationPolicy):
        (WebCore::FrameLoader::checkLoadCompleteForThisFrame):

        * page/FrameTree.cpp:
        (WebCore::FrameTree::removeChild):

        * page/Page.cpp: Transfered a handful of concepts from WebView
        (WebCore::Page::Page):
        (WebCore::Page::~Page):
        (WebCore::Page::backForwardList):
        (WebCore::Page::goBack):
        (WebCore::Page::goForward):
        (WebCore::Page::goToItem):
        * page/Page.h:

        * page/PageState.h:
        * page/mac/FrameMac.h:
        * page/mac/FrameMac.mm:
        * page/mac/WebCoreFrameBridge.h:
        * page/mac/WebCoreFrameBridge.mm:

        * platform/KURL.cpp:
        (WebCore::KURL::print):  Added debug only method for debugging convenience
        * platform/KURL.h:

        * platform/Logging.cpp:
        (WebCore::): Added some logging channels
        * platform/Logging.h:

        * platform/PlatformString.h:
        (WebCore::nsStringNilIfEmpty): Added for WebKit use

        * platform/SystemTime.h: Added userIdleTime()

        * platform/graphics/svg/SVGImage.cpp:
        * platform/graphics/svg/SVGImageEmptyClients.h: Updated for new FrameLoaderClient methods
        (WebCore::SVGEmptyFrameLoaderClient::setDocumentViewFromPageCache):
        (WebCore::SVGEmptyFrameLoaderClient::updateGlobalHistoryForStandardLoad):
        (WebCore::SVGEmptyFrameLoaderClient::updateGlobalHistoryForReload):
        (WebCore::SVGEmptyFrameLoaderClient::shouldGoToHistoryItem):
        (WebCore::SVGEmptyFrameLoaderClient::saveScrollPositionAndViewStateToItem):
        (WebCore::SVGEmptyFrameLoaderClient::saveDocumentViewToPageCache):
        (WebCore::SVGEmptyFrameLoaderClient::canCachePage):
        (WebCore::SVGEmptyEditorClient::~SVGEmptyEditorClient):

        * platform/mac/LoggingMac.mm:
        (WebCore::InitializeLoggingChannelsIfNecessary):

        * platform/mac/SystemTimeMac.cpp:
        (WebCore::userIdleTime):

        * platform/mac/WebCoreSystemInterface.h: Added wkSecondsSinceLastInput for use in userIdleTime
        * platform/mac/WebCoreSystemInterface.mm:

        * platform/network/FormData.cpp:
        (WebCore::FormData::FormData):
        (WebCore::FormData::copy):
        * platform/network/FormData.h:

        * platform/network/ResourceHandle.h:
        * platform/network/mac/ResourceHandleMac.mm:
        (WebCore::ResourceHandle::willLoadFromCache): For "are you sure you want to resubmit?" nag

        * platform/qt/TemporaryLinkStubs.cpp:
        (WebCore::userIdleTime):
        * rendering/RenderPart.h:

WebKit:

        Reviewed extensively and repeatedly by Darin

        <rdar://problem/4887137> - WebCore Back/Forward Cache 
        Most things not specifically commented on in the ChangeLog can be summed up as 
        "Do things exactly the same way as we used to, but just stick in WebCore-land as much as possible"

        * History/WebBackForwardList.mm:
        (kitPrivate): Convenience functions to help with subbing "WebBackForwardListPrivate" for WebCore::BackForwardList
        (core):
        (backForwardListWrappers): A HashMap pattern used to map WebCore objects to their WebKit counterpart
        (kit):
        (+[WebBackForwardList setDefaultPageCacheSizeIfNecessary]):
        (-[WebBackForwardList initWithWebCoreBackForwardList:]):
        (-[WebBackForwardList init]):
        (-[WebBackForwardList dealloc]):
        (-[WebBackForwardList finalize]):
        (-[WebBackForwardList _close]):
        (-[WebBackForwardList addItem:]):
        (-[WebBackForwardList removeItem:]):
        (-[WebBackForwardList containsItem:]):
        (-[WebBackForwardList goBack]):
        (-[WebBackForwardList goForward]):
        (-[WebBackForwardList goToItem:]):
        (-[WebBackForwardList backItem]):
        (-[WebBackForwardList currentItem]):
        (-[WebBackForwardList forwardItem]):
        (vectorToNSArray):
        (-[WebBackForwardList backListWithLimit:]):
        (-[WebBackForwardList forwardListWithLimit:]):
        (-[WebBackForwardList capacity]):
        (-[WebBackForwardList setCapacity:]):
        (-[WebBackForwardList description]):
        (-[WebBackForwardList _clearPageCache]):
        (-[WebBackForwardList setPageCacheSize:]):
        (-[WebBackForwardList pageCacheSize]):
        (-[WebBackForwardList _usesPageCache]):
        (-[WebBackForwardList backListCount]):
        (-[WebBackForwardList forwardListCount]):
        (-[WebBackForwardList itemAtIndex:]):
        * History/WebBackForwardListInternal.h: Added.

        * History/WebHistory.m: Removed.
        * History/WebHistory.mm: Added - Needed to be .mm to accept C++ header style
        (-[_WebCoreHistoryProvider containsItemForURLLatin1:length:]):
        (-[_WebCoreHistoryProvider containsItemForURLUnicode:length:]):

        * History/WebHistoryItem.mm:
        (kitPrivate): Same pattern as WebBackForwardList
        (core):
        (historyItemWrappers):
        (WKNotifyHistoryItemChanged):
        (-[WebHistoryItem init]):
        (-[WebHistoryItem initWithURLString:title:lastVisitedTimeInterval:]):
        (-[WebHistoryItem dealloc]):
        (-[WebHistoryItem finalize]):
        (-[WebHistoryItem copyWithZone:]):
        (-[WebHistoryItem URLString]):
        (-[WebHistoryItem originalURLString]):
        (-[WebHistoryItem title]):
        (-[WebHistoryItem setAlternateTitle:]):
        (-[WebHistoryItem alternateTitle]):
        (-[WebHistoryItem icon]):
        (-[WebHistoryItem lastVisitedTimeInterval]):
        (-[WebHistoryItem hash]):
        (-[WebHistoryItem isEqual:]):
        (-[WebHistoryItem description]):
        (kit):
        (+[WebHistoryItem entryWithURL:]):
        (+[WebHistoryItem initWindowWatcherIfNecessary]):
        (-[WebHistoryItem initWithURL:target:parent:title:]):
        (-[WebHistoryItem initWithWebCoreHistoryItem:]):
        (-[WebHistoryItem setTitle:]):
        (-[WebHistoryItem setVisitCount:]):
        (-[WebHistoryItem setViewState:]):
        (-[WebHistoryItem _mergeAutoCompleteHints:]):
        (-[WebHistoryItem initFromDictionaryRepresentation:]):
        (-[WebHistoryItem scrollPoint]):
        (-[WebHistoryItem _transientPropertyForKey:]):
        (-[WebHistoryItem _setTransientProperty:forKey:]):
        (-[WebHistoryItem dictionaryRepresentation]):
        (-[WebHistoryItem target]):
        (-[WebHistoryItem isTargetItem]):
        (-[WebHistoryItem visitCount]):
        (-[WebHistoryItem RSSFeedReferrer]):
        (-[WebHistoryItem setRSSFeedReferrer:]):
        (-[WebHistoryItem children]):
        (-[WebHistoryItem setAlwaysAttemptToUsePageCache:]):
        (-[WebHistoryItem URL]):
        (-[WebHistoryItem _setLastVisitedTimeInterval:]):
        (-[WebHistoryItem _lastVisitedDate]):
        (-[WebHistoryItem targetItem]):
        (+[WebHistoryItem _releaseAllPendingPageCaches]):
        (-[WebWindowWatcher windowWillClose:]):
        * History/WebHistoryItemInternal.h:
        * History/WebHistoryItemPrivate.h:

        * WebCoreSupport/WebFrameBridge.mm:
        * WebCoreSupport/WebFrameLoaderClient.h:
        * WebCoreSupport/WebFrameLoaderClient.mm:
        (WebFrameLoaderClient::setDocumentViewFromPageCache):
        (WebFrameLoaderClient::detachedFromParent1):
        (WebFrameLoaderClient::loadedFromPageCache):
        (WebFrameLoaderClient::updateGlobalHistoryForStandardLoad):
        (WebFrameLoaderClient::updateGlobalHistoryForReload):
        (WebFrameLoaderClient::shouldGoToHistoryItem):
        (WebFrameLoaderClient::frameLoadCompleted):
        (WebFrameLoaderClient::saveScrollPositionAndViewStateToItem):
        (WebFrameLoaderClient::restoreScrollPositionAndViewState):
        (WebFrameLoaderClient::provisionalLoadStarted):
        (WebFrameLoaderClient::setTitle):
        (WebFrameLoaderClient::saveDocumentViewToPageCache):
        (WebFrameLoaderClient::canCachePage):

        * WebCoreSupport/WebSystemInterface.m:
        (InitWebCoreSystemInterface):

        * WebKit.xcodeproj/project.pbxproj:

        * WebView/WebDataSource.mm:
        * WebView/WebDataSourceInternal.h:

        * WebView/WebFrame.mm:
        (-[WebFramePrivate dealloc]):
        (-[WebFrame _canCachePage]):
        (-[WebFrame _loadURL:referrer:intoChild:]):
        * WebView/WebFrameInternal.h:

        * WebView/WebFrameView.mm:
        (-[WebFrameView initWithFrame:]):
        (-[WebFrameView keyDown:]):

        * WebView/WebHTMLView.m:
        (-[WebHTMLView closeIfNotCurrentView]): Added for a dirty hack in WebCore that is marked with a FIXME Radar
        * WebView/WebHTMLViewInternal.h:

        * WebView/WebView.mm:
        (-[WebViewPrivate init]):
        (-[WebViewPrivate dealloc]):
        (-[WebView _close]):
        (-[WebView _loadBackForwardListFromOtherView:]):
        (-[WebView _commonInitializationWithFrameName:groupName:]):
        (-[WebView initWithCoder:]):
        (-[WebView backForwardList]):
        (-[WebView goBack]):
        (-[WebView goForward]):
        (-[WebView goToBackForwardItem:]):
        (-[WebView canGoBack]):
        (-[WebView canGoForward]):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@18541 268f45cc-cd09-0410-ab3c-d52691b4dbfc