First checkin of making frames work with the back forward list, restoring scroll position and form state.  Fixing:

3014555 Lose frameset context going back/forward
3078151 History inconsistency after loading frame content
3089551 REGRESSION: www.bmwusa.com frames don't load in alex-30
3095878 refresh doesn't preserve frame state

WebCore:

        * khtml/khtml_part.cpp:
        (KHTMLPart::requestFrameName):  Call through bridge to get generated frame name.
        * kwq/KWQKHTMLPart.h:
        * kwq/KWQKHTMLPart.mm:
        (KWQKHTMLPart::generateFrameName):  New call that just forwards through the bridge.
        * kwq/WebCoreBridge.h:

WebKit:

        * History.subproj/WebBackForwardList.m:
        (-[WebBackForwardList addEntry:]):  Yank code to avoid adding a duplicate entry, to catch the
	refresh case.  That's dealt with in WebFramePrivate now.
        (-[WebBackForwardList description]):  Enhanced to print more info.

        * History.subproj/WebHistoryItem.h:
	History items now hold an array of subitems to mirror the frame tree.  One item in the tree
	is designated the target of the navigation.
        * History.subproj/WebHistoryItem.m:
        (-[WebHistoryItem dealloc]):  Release new ivars.
        (-[WebHistoryItem isTargetItem]):
        (-[WebHistoryItem setIsTargetItem:]):
	New setter and setter.
        (-[WebHistoryItem _recurseToFindTargetItem]):
        (-[WebHistoryItem targetItem]):
	Search the tree to find the target item.
        (-[WebHistoryItem children]):
        (-[WebHistoryItem addChildItem:]):
        (-[WebHistoryItem childItemWithName:]):
	Maintain and search new child item list.
        (-[WebHistoryItem description]):
	Enhanced to print out the tree of items.
        (-[WebHistoryItem dictionaryRepresentation]):
        (-[WebHistoryItem initFromDictionaryRepresentation:]):
	Save and load the new state.

        * WebCoreSupport.subproj/WebBridge.m:
        (-[WebBridge generateFrameName]):  New call from KWQ, just forwards to Frame.
        (-[WebBridge createChildFrameNamed:withURL:renderPart:allowsScrolling:marginWidth:marginHeight:]):
	Call new frame method dedicated to this case.
        (-[WebBridge saveDocumentState:]):
        (-[WebBridge documentState]):
	Call frame methods to get the right item to save/restore to/from.

        * WebView.subproj/WebController.m:
        (-[WebController _goToItem:withLoadType:]):  Stop any current loading before going to a new item.
        (-[WebController goBack]):
        (-[WebController goForward]):
        (-[WebController goBackOrForwardToItem:]):  Name change of private method (for consistency)

        * WebView.subproj/WebDataSourcePrivate.h:
	ProvisionalItem and PreviousItem are moved back up to WebFrame, where we know more about the
	state transitions that happen during loading.
        * WebView.subproj/WebDataSourcePrivate.m:
        (-[WebDataSourcePrivate dealloc]): Don't release removed ivars.
        (-[WebDataSource _commitIfReady]): Make the view representations -after- the transition to committed.
	This allows us to save away the scroll location successfully, since making the view was resetting it.
        * WebView.subproj/WebFrame.h:
        * WebView.subproj/WebFrame.m:
        (-[WebFrame setProvisionalDataSource:]):  Saving the scroll location has moved elsewhere to handle frames.
        (-[WebFrame stopLoading]):  Skip all the work if we're already state=complete.

        * WebView.subproj/WebFramePrivate.h:
	The frame now holds a ref to the current, previous and provisional back-forward items.
        * WebView.subproj/WebFramePrivate.m:
        (-[WebFramePrivate dealloc]):  Release new state.
        (-[WebFramePrivate setProvisionalItem:]):
        (-[WebFramePrivate setPreviousItem:]):
        (-[WebFramePrivate setCurrentItem:]):	New setters (1 line getters were missed by script)
        (-[WebFrame _addBackForwardItemClippedAtTarget:]):  Adds a BF item to the top of the BF list.
        (-[WebFrame _createItem]):  Create a single BF item.
        (-[WebFrame _createItemTreeWithTargetFrame:clippedAtTarget:]):  Create a tree of BF items, which
	mirror the frame tree.
        (-[WebFrame _immediateChildFrameNamed:]):  New frame search utility (doesn't recurse)
        (-[WebFrame _detachFromParent]):  Save the scroll position when detaching a frame.
        (-[WebFrame _transitionToCommitted]):  Maintain new item ivars.  Save scroll position when
	appropriate.  Hook up items for child frames to their parent, as they are created.
        (-[WebFrame _setState:]):  Clear previousItem whenever we reach committed.
        (-[WebFrame _isLoadComplete]):  Clear previousItem if we are committed.
        (-[WebFrame _childFramesMatchItem:]):  Does the frame's frame tree match the one held by the item?
        (-[WebFrame _loadItem:fromItem:withLoadType:]):  Only do simple anchor navigation if the frame
	has no children (fixes oddball corner case with a frame reloading itself).  Set provisional item.
        (-[WebFrame _recursiveGoToItem:fromItem:withLoadType:]):  Heart of returning to an item that had
	frames.  We either find that the existing content is good, or initiate a load.
        (-[WebFrame _goToItem:withLoadType:]):  Adjust the BF list cursor, and recurse to do the work.
        (-[WebFrame _loadURL:loadType:clientRedirect:triggeringEvent:]):  Only do anchor-style nav if
	the destination URL has a fragment.  Save scroll position.
        (-[WebFrame _loadURL:intoChild:]):  If returning to an item with frames, possibly replace the
	new content with the stuff that was there at the time, substituting the URL.
        (-[WebFrame _saveScrollPositionToItem:]):  Don't croak on nil item or view.
        (-[WebFrame _restoreScrollPosition]):  Do croak (ASSERT) on nil item.
        (-[WebFrame _scrollToTop]):  Nit cleanup.
        (-[WebFrame _addFramePathToString:]):  Add a component for our frame to the frame name we're generating.
        (-[WebFrame _generateFrameName]):  Generate a frame name that is repeatable.
        (-[WebFrame _itemForSavingDocState]):  Returns correct item to use for formstate save.
        (-[WebFrame _itemForRestoringDocState]):  Returns correct item to use for formstate restore

WebBrowser:

        * BrowserDocument.m:
        (-[BrowserDocument _addItem:toMenu:]):
	For a back-forward item that's a tree because its for a frameset, use the
	right item of the tree to generate the menu contents.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@2624 268f45cc-cd09-0410-ab3c-d52691b4dbfc